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This report was superseded in October, 2011.

This section begins with a reflection on the academic literature in its relation to the concept of megaregions for transportation planning and operations. It concludes by examining methods that have been used to delineate the boundaries of different types of regions, especially megaregions.

A. Examining the Literature

The megaregions concept is a relatively new area of academic pursuit: there exist only a limited number of peer-reviewed articles and books on the subject. However, there is a breadth of writing on topics closely related to megaregions including discussions of regionalism, globalization, global climate change, governance, economic geography, and spatial planning.

1. Regionalism

Currently, major issues and concerns facing regions in the United States are typically addressed at a level dictated by jurisdiction rather than function. However, in many instances the spatial dimensions defining functions have surpassed traditional jurisdictional boundaries, creating new and dynamic patterns of urban space and functionality at metropolitan and regional levels (Salet et al., 2003a). For example, development patterns in one jurisdiction may lead to traffic congestion in another, which may lead to air quality and health problems in yet another. All of these issues are interrelated, yet the decision-making and planning happens at the individual jurisdiction's discretion with suboptimal results for all parties concerned. This implies that functional relationships already exist in space, but the planning for these relationships often does not. Thus, planning for and discussion of these functional relationships is not taking place at the same scale as the relationships themselves.

This is not to say that the spatial mismatch between jurisdiction and functionality has been completely ignored. Over the past century in the United States, there have been many discussions of planning and addressing problems on various regional scales (Wheeler, 2002; Levine, 2001). In recent decades, regional planning and advocacy of regional approaches have focused more on potential economic benefits, with assertions that regionalism will lead to greater economic growth, even though these economic benefits have not always been readily apparent (Levine, 2001).

Some regional cooperation, particularly at the economically functional level, is already happening in the United States. This is primarily occurring in areas of service delivery, including parks and recreation, transportation, and wastewater treatment (Gyourko, 1997). But this cooperation, while providing some economic benefits (primarily through greater efficiencies and economies of scale), is somewhat singularly focused and has not been a panacea for urban or fiscal problems happening at the same scale, such as concentration of poverty, housing affordability, or lack of health-care coverage (Gyourko, 1997, Levine, 2001).

The nature of our existing regional planning focus, while based on economics, is not explicitly spatial (Levine, 2001). Therefore, as regions continue to expand into megaregions, the planning functions and underlying incentives for cooperation are not expanding accordingly.

Whether this lack of spatial focus is a function of the capacity of regionalism per se or a symptom of a different issue is not clear. One possible reason for the perceived inability of regionalism to address the previously mentioned problems is suggested by Barnes & Ledebur (1998; cited by Levine 2001: p.191):

Local decisions are often driven primarily by highly localized interests, which can result in minimal improvements in productivity and competitiveness at great cost; that is, political autonomy creates a false sense of economic autonomy and produces decisions that are often zero-sum or even negative-sum for the region as a whole.

The space of economic functionality is thus not promoted because decision-making entities and governance functions are based on legal jurisdiction and not on the economically functional region. There are no explicit incentives for addressing the broader spatial implications of local issues outside of the localized interests driving many of the decision-making processes. This deficiency of explicit incentives leads to a lack of focus on the space affected by economic decisions, even while the effects of these economic decisions on space are continually expanding. Indeed, Barnes and Ledebur (1998) suggest that current incentives to promote inter-jurisdictional cooperation are limited to four instances:

Currently, transfer of resources between a city and its surrounding regions is often treated by decision-makers as an externality; only with explicit economic benefit or jurisdictional requirement will jurisdictions cooperate (Gyourko, 1997). As such, any potential benefits resulting from cooperation between these areas may not be considered in planning or the decision-making process, producing, as Levine (2001) suggests, counter-productive results. This implies that planning at an economically functional level, regardless of the scale, will only occur when the direct economic benefit of that planning is clear to decision-makers or the proper incentives are implemented.

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2. Globalization

The growth and complexity of megaregions exerts influence on multiple economic scales: local, regional, national, and global. Additionally, regional economies are expanding in focus and becoming more influenced by global forces. Increasingly, cities and their surrounding regions do not function as islands (Jensen & Richardson, 2001). Salet et al. (2003a) suggest that "regional economies have become more dependent on their position in global networks than on the traditional powers and investments of local industries and local entrepreneurs."

With respect to regional growth and competitiveness, what happens outside the region may be as important as what happens inside the region. Regions, especially those that can offer a diversity of skills, innovation and production while remaining relatively flexible, are becoming increasingly engaged in global trade (Levine, 2001). This has led to, in some cases, the economies of regions driving the national economy rather than the traditional macroeconomic thought of national economies shaping the region (Levine, 2001). Additionally, Porter (2001, p. 156) has argued that "[p]rosperity in the modern, global economy is increasingly rooted in the micro-economic capacity of economic areas." Thus, the region as an economic entity is becoming a primary force in the global economy. Recent work by Sassen (2007) suggests that the presence of multiple types of agglomeration economies within one regional space goes beyond "familiar scale economies and associated urbanization advantages" allowing us to reasonably expand the aforementioned ideas about regional spaces to those of the megaregion.

While regions continue to expand in economic scale and functionality, increasingly complex economic functional relationships are expanding spatially, reaching beyond and across current jurisdictional and decision-making boundaries. This expanding scope is seen in the sprawling growth patterns throughout the United States in the past few decades, as urban functions can be seen in traditionally non-urban forms such as suburbs and exurbs (Lang and Dhavale, 2005).

As these urban functions continue to spread into traditionally non-urban areas, so do the spatial ramifications of these functions. Regional planning, as a measure of regional coordination, is a factor that positively affects the economic welfare of the region (Levine, 2001). A region's success at competing on a global scale thus must be linked to its ability to coordinate and plan for economic functionality. The increasing recognition of regions as the economic footprint of the global economy suggests the megaregion approach may be helpful in responding to the challenges outlined above.

While the case can be made for a spatial focus in planning a region's economic function, it is not only economics driving economic functionality and dictating the spatial effect of a region. Regional transportation, land availability, economic competition, housing availability and affordability, environmental issues, natural resources management, and quality of life are all interlinked throughout the region. Porter (2001) argues that environmental and social issues are inextricably linked to a region's economic functionality. Therefore, as a region's economic functionality increases, so do the associated environmental and social concerns. Alleviating the many issues - including those that are environmental and social in nature - will require their integration in the economic discussions at a megaregional level (Porter, 2001). In other words, a holistic, spatially-based approach to regional planning has the potential to allow megaregions to succeed in an increasingly global marketplace.

Megaregions are more than just physical connections, economic agglomerations or heavily populated places; megaregions are connections to each other and to the people that live within them and to the places they traverse. As such, the social obligations that we assume in the global economy are also important. For economically depressed areas, impoverished populations, or places that do not have adequate service provision or access to markets, the new challenges of infrastructure and megaregions are to be an umbrella under which we meet our needs (Edgington et al., 2001).

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3. Global Climate Change

At this point in time it is much easier to list the current and potential impacts of transportation on rising global temperatures (often referred to simply as "climate change") than to state clearly and definitively what actions should be taken to mitigate these impacts. This section has two goals: first, to discuss how current transportation patterns in the United States contribute to the production of greenhouse gases (GHGs) and thus to rising global temperatures and their climatic effects; and second, to make some preliminary speculations on how refocusing transportation planning along megaregional lines might affect the relationship between transport and GHGs.

Rising average global temperatures are believed to have a number of consequences, including, but not limited to, melting of the polar ice caps, rises in average sea level, changes in the hospitality of habitats to plant or animal life, and increased instability of areas of permafrost (IPCC, 2007). Figure 1 shows how average surface temperature, sea level, and snow cover in the Northern Hemisphere changed between 1850 and 2000 (IPCC, 2007).

These changes are believed to be positively correlated with the increased emissions of GHGs related to human activity, particularly carbon dioxide (CO2). Between 1971 and 2001, CO2 emissions worldwide rose by 60% (Banister, 2005). Figure 2 shows increases in production of CO2 and three other GHGs - methane, or CH4; nitrous oxide, or N2O; and "F-gases," or gases including fluoride, such as hydrofluorocarbons - since 1970.

Three graphs of changes in selected global environmental indicators between 1850 and 2000.  The first shows global annual surface temperature varying little between 1850 and 1900, increasing gradually between 1900 and 1950, and then increasing more rapidly between 1950 and 2000. The second shows that global average sea level has been increasing steadily since 1870. The third shows that snow cover in the Northern Hemisphere has been decreasing since 1920, with the biggest drop since 1980.

Transport is one of the largest producers of GHG emissions, particularly CO2 emissions. Worldwide, fuel combustion accounted for 25 billion tons of CO2 emissions in 2003 (TRB, 2008). During that time U.S. emissions were 1.8 billion tons, of which 85% could be attributed to road transport (TRB, 2008). The rise in GHG emissions can be correlated with increasing globalization and increases in inter-regional and international trade (van Veen-Groot and Nijkamp, 1999). It is reasonable to expect that decisions in transport policy will have an impact on US GHG emissions, which could in turn have an impact on worldwide average temperatures.

What would scaling transport to the megaregional level imply in terms of climate change? There are currently two major types of responses to climate change: "mitigation," which consists of strategies to reduce GHG emissions and thus slow the contribution of GHG emissions to climate change, and "adaptation," which consists of strategies in response to changes in weather patterns related to climate change. A megaregion approach has implications for both mitigation and adaptation strategies, each of which is considered in the following paragraphs.

Since approximately 80 percent of the world's carbon emissions are produced from urbanized areas (Aitch, 2007), it is reasonable to assume that megaregions have a significant impact on the increase of carbon emissions. At the same time, this means the megaregion approach could be a solution to reduce the world's carbon emissions. The following megaregion approaches could be considered such strategies. First of all, megaregion development, centered as it is around major urban centers, could encourage land-use patterns that in turn lead to higher-density development. One study has suggested that denser land uses could lead to a 10% reduction in urban transport activity in the United States (Grazi et al., 2008). As the "diffused metropolis" (Camagni et al., 2002) is more difficult to serve by public transport, denser development could lead to greater uses of public transport and a less predominant role of private cars. But it should be emphasized that at this point such changes in land use are the result of speculation. Currently, different megaregions have different land use policies and it is possible to speculate that different megaregions will probably continue to have different land-use patterns. However, land use planning in primary corridors in the megaregions could possibly benefit from a regional perspective on land use along those corridors linking the economic centers of these regions. Such an approach could be part of a national strategy for assuring mobility within these corridors.

A second possibility is that the megaregion could be used to coordinate transport pricing policies. England (2007) raises this possibility with his simulation of an increase in the gasoline tax of 50 cents per gallon in six New England states. The simulation compared the enacting of the increase by the six states individually, to its being enacted simultaneously. The results of the simulation suggested that the positive benefits of such a tax are increased if the six states enact the increase simultaneously: environmental benefits increase and a higher portion of the fiscal stimulus remains within the region. England chose six states in New England for his simulation on the grounds that the region has a relatively extensive transport system, affluent travelers, and local political actors committed to reducing GHG emissions. This analysis suggests that megaregions could, given sufficient political coordination, take advantage of shared local concerns to enact mitigation policies.

Yet a third possibility is that megaregion transport planning could lead to changes in freight transport patterns. Designing transport systems with regional, rather than local, industry patterns in mind might make it easier to, first, increase efficiencies of shipping, thereby reducing congestion and related GHG emissions, and second, shift more freight shipping from truck to rail. Forkenbrock (2001) showed that the costs per ton-mile (in 1994 cents) of GHG emissions for rail freight were just 13% of those for trucks. Again, such coordination would vary depending on the resources, industrial location patterns, and specializations of the megaregion.

Three charts on global anthropogenic GHG emissions.  The first is a bar chart showing rises in pollutants such as carbon dioxide, methane, and nitrous oxide.  The second is a pie chart showing the composition of emissions, dominated by carbon dioxide at 76.7% of total emissions; other sources of emissions include methane and nitrous oxide.  The third shows how emissions are generated: mostly comes from energy supply industry, forestry, agriculture, and transport.

The megaregion could also play a role in adaptation strategies. The Transportation Research Board of the National Academies (2008) has detailed a series of predictions as to how climate change might affect transportation infrastructure:

Climate change is associated with a variety of extreme climate events. Disaster as a result of Hurricanes Katrina and Rita and the displacement of victims along the Gulf Coast megaregion demonstrated the links between transportation infrastructure and environments in the region (RPA, 2006). A megaregion approach could play a role to efficiently meet these challenges. The Transportation Research Board report also concluded that regional coordination will be necessary to help adapt existing and new transportation infrastructure to the demands of more extreme climate events:

Adapting successfully to climate change will require forging new partnerships and organizational arrangements that better align with the impacts of climate change, which do not follow modal, jurisdictional, or corporate boundaries… The creation of regional and multistate organizational arrangements to address climate change is a formidable challenge, but could yield enormous payoffs in the ability to respond not only to climate change, but also to other natural and manmade disasters. (TRB, 2008)

In sum, megaregions could be a useful tool to in deciding both how to adapt to climate change and its impacts and how to decrease GHG emissions in order to slow the correlated increase in global temperatures. However, both the study of megaregions and the study of climate change remain relatively young and there may be even more opportunity to achieve a more sustainable outcome.

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4. Economic Geography

Concurrent with the rise and focus on the increasing significance of regions in the global economy is a resurgence of interest in economic geography. This is focused on economic activities and identifying, measuring, and locating agglomerative effects. There are cultural events, social affiliations, and racial enclaves that are also correlated with the agglomerative effects of megaregions. Therefore, the concept of the megaregion has become a topic in the expanding interest in economic geography (see Sassen (2007) and Glaeser (2007)).

Economic growth, industry organizations and global trends, transactions, and commerce underlie and give rise to the increasing focus on economic and spatial geography. As importantly, the difference between developed urban spaces that are thriving economically, and those that have less economic activity can be investigated within the context of economic geography. More importantly, in this global market there is a continued expectation of increasing revenues and growth that can be enhanced through recognition of place and its ability to attract other sectors critical to its continued development. Megaregions are places that operate at the center of a new economic geography.

The economic geography (and by extension, functionality) of regions arises in large part from agglomeration economies (Fujita et al., 1999). The economic geography of megaregions can be thought of as agglomerations of agglomeration economies. Agglomeration results in the clustering of economic activities and associated effects, but this is offset with expansion forces simultaneously spreading the activities effects of agglomeration, in a type of circular causation (Fujita et al., 1999).

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5. Spatial Planning

As the concept of megaregions and an underlying framework for spatial planning is discussed and pursued in the United States, it will prove beneficial to study spatial planning undertaken in the European Union (EU). In many ways, Europe is dealing with many of the same issues facing the United States - expanding and changing urban structures outgrowing traditional jurisdictional boundaries and a rapidly globalizing marketplace where the region as a whole is becoming an economic entity (Salet et al., 2003a). These issues have intensified with the changes brought about by the creation and expansion of the EU.

Spatial planning begins with spatial policy, which is "any policy which is spatially specific or is in effect spatial in practice, whether or not it is deliberately designed to be, and any policy which is designed to influence land-use decisions, to be integrated with local planning strategies or to be implemented by local and regional authorities as part of their spatial planning responsibilities" (Williams, 1996, 7). Hence, according to the European Regional/Spatial Planning Charter, spatial planning is "conducted through a very systematic and formal hierarchy of plans from national to local level, which coordinate public sector activity across different sectors but focus more specifically on spatial coordination than economic development" (Council of Europe, 1984).

Spatial planning has long occurred in Europe. With the advent of the EU, spatial planning is becoming more defined and is taking place on a larger scale with planning often crossing jurisdictional and sometimes even national boundaries (Jensen & Richardson, 2001; Nadin, 2001; Salet et al., 2003a). Two documents in particular provide guidance in developing governance and planning frameworks by looking at various cases of spatial planning in Europe: "Governance of Territorial and Urban Policies from EU to Local Level" (ESPON, 2006) and "A Framework for City Regions" (Harding et al., 2006), published by the British Office of the Deputy Prime Minister. Both of these documents were created to provide an evidence base for a sustainable framework for regional spatial planning. This guidance provides valuable lessons for multiple scales of spatial planning but is particularly useful when thinking of frameworks for inter-jurisdictional planning areas such as megaregions.

Although all of these planning efforts have different approaches and different spatial scales, they are based on the belief that regional performance plays a role in both the domestic and global functioning of the national economy and in the quality of life of the residents (Harding et al.,2006). The EU uses these large-scale planning frameworks to promote social equity and to strengthen regions and make them more economically competitive globally.

These planning efforts are rooted in spatial visioning, which is also seen as spatial planning strategy (Nadin, 2001; ESPON, 2006). The primary goals of this spatial planning process are to understand long-term spatial development trends, create options for the development of the territorial structure of an area, and inspire and guide the spatial planning process (Nadin, 2001). This is all done while bringing together the objectives of economic and social cohesion, conservation of natural resources and cultural heritage, and the balanced competitiveness of space (ESPON, 2006).

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6. Governance

Governance is the process by which society and organizations make decisions, determine representation, and render accountability. Governance is not synonymous with government, because it involves people and organizations outside governmental entities (Graham et al., 2003). It is a complex process, with many different actors playing multiple roles.

Throughout the United States the division of responsibility between federal, state, county or parish, metropolitan, and local agencies leads to the fragmentation of actions and policies. Each entity has powers and responsibilities given to it by the state. These powers and responsibilities include but are not limited to: public safety, taxation, and planning. Each state grants different powers to its counties and municipalities. The differences in state systems increase the complexity, making cooperation among layers of government and different states a challenge and decreasing incentives to develop complementary polices and regulations.

In addition to the complex layers of government, there are also multiple entities beyond those typically associated with government, which also impact planning. The spatial context of planning efforts varies, but most comprehensive planning is done at the local level, and focuses on parochial interests. There are regional planning entities, but these units of governance typically focus on a single problem, and rarely cross state boundaries.

Even within a single government entity there is often functional fragmentation. Governmental fragmentation refers to the raw numbers of government entities in any given region. Functional fragmentation is the division of duties by discipline and by problem. The internal fragmentation of government fails to recognize the fact that problems are often related. As a result, "goals, objectives and policies are considered and administered within the confines of their specific functional areas" (Krizek & Powers, 1996, p.24).

Government fragmentation also enhances inter-jurisdictional competition. Communities compete for desirable commercial and industrial development and the accompanying perceived contribution to the tax base: "[O]ne community's gain is likely to be another's loss" (Orfield, 2002a, p.91). While such competition at the local level is sometimes desirable for economic development policy in that it promotes a removal of government regulations and a local control is flexible to react to local realities (Glaeser, 2007), there may be limitations for local governments to face with challenges in a global markets. In addition, state governments also compete at the federal level for transportation, education and other social welfare grants. The task for megaregional approaches is to overcome the challenges these fragmented approaches pose.

Intergovernmental relationships in the United States are characterized by interdependence, complexity and bargaining (O'Toole & Laurence, 2000). Specialists in agencies, legislative committees and pressure groups all seek to gain influence in a maze too complex for any one official or citizen to comprehend. It is "increasingly difficult for anyone, even major officials like governors or mayors or presidents, to decipher just who [is] causing what to happen" (O'Toole & Laurence, 2000, p.18, emphasis in original). Power is shared between levels of government, both vertically and horizontally, and "any change requires mutual accommodation" (O'Toole & Laurence, 2000, p.19), diluting and diffusing the original intent. The impacts of this complexity and accommodation on the future sustainability in megaregions relate to the ability of actors to take action when decisive action is needed. It is increasingly difficult to craft a unifying vision, develop a singular policy approach and "systematically execute positive action in a straightforwardly rational manner" (O'Toole & Laurence, 2000, p.19, emphasis in original).

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7. Informing a Megaregion Framework

The aforementioned literature suggests a potentially fruitful, yet challenging, path for megaregions from a policy and governance perspective. The exact nature of regional functional economic relationships is complex and not easily measured through current means, making it difficult to understand the regional economic interaction (Hoover, 1971). Inasmuch as this economic functionality and the underlying economic relationships can be understood, one could infer the existence of implicit incentives for a region to cooperate on economic grounds. To do this, it is important to understand these agglomeration economies and the need for their continued growth (Fujita et al., 2001). The previously mentioned instances of inter-jurisdictional cooperation suggested by Barnes & Ledebur (1998) could potentially allow for spatial focus and planning at the scale of economic functionality on an inter-jurisdictional level. If this were to occur, it could lead to economic decisions being made at the appropriate spatial level which could potentially offset the negative repercussions - zero- or negative-sum decisions (Levine, 2001) - of the autonomous local thinking that leads to inefficient regional economic activity and public investment.

What role do mobility and transportation infrastructure play in the development and success of megaregions in the global context? While the role of infrastructure in developing countries is a commonplace topic, the use of infrastructure in highly developed countries and its role in expanding economic activity has not received the same amount of attention (Edgington et al., 2001). Infrastructure should be designed and created to support our global markets, as well as provide the social infrastructure to sustain our lives, families and communities. There have been numerous strategies and views put forward outlining the significance and importance of regional planning to expand economic influence and the role of infrastructure in accomplishing that effectively (Edginton et al., 2001; Isard et al., 1998; Dreier et al., 2001).

Infrastructure is the skeleton linking towns, cities, and neighborhoods to regions, regions to megaregions, and megaregions and countries together. More explicitly, transportation and mobility hubs have historically proven to be advantages to our cities and, by extension, regions (Fujita et al., 2001).

The consideration of regional economic growth sets the stage for the development of a spatial planning framework as a tool for the success of megaregions within the United States. With a multi-sectoral, place-based spatial planning approach, it is feasible to explicitly address economic prosperity as well as social and environmental issues in a megaregion framework. But this framework should go beyond merely a normative assertion. Historically, regional reform has been argued from theoretical and normative perspectives rather than from a base of empirical findings; this approach has left regional economic development detached from spatial reality (Levine, 2001). While a normative argument must be made for a holistic approach to regional planning, there must also be an empirical study of the realities of the interconnectedness of environmental, social, and economic functions and operations at the megaregion level.

Spatial planning plays a key role in coordinating policy and practice at multiple scales. But the obstacles to creating a spatial-planning framework are highly interconnected and cannot be overcome piecemeal; rather, the planning process must address all three to succeed. First, there must be a change in the understanding of megaregions and the functional and infrastructural connections between them. Second, it is necessary to develop effective, widely-supported governance arrangements that can mobilize, sensitize, and align national, megaregion, state, regional, and local actors. And third, effective spatial planning will require more coordination of public sector investment and expenditure over the long term to provide benefits and incentives for inter-jurisdictional cooperation.

The increasing importance of the region as a driver in the larger national and thus the global economy is well known. Therefore, it is important to have a national vision for how megaregions interact on an economic scale, and by extension on a functional scale. This greater understanding of the interconnectedness of megaregions, especially through transportation systems, can allow for the development of an incentive framework that jointly pushes the advancement of economic, environmental, and social goals.

The EU has seen more participation in the spatial planning process, especially from private sector and stakeholders at all levels, when benefits to those stakeholders are clearly recognizable. Many of the successful examples of increased collaboration resulting in joint spatial development plans or visions were generated through a pragmatic need for interaction in functional regions covering increasingly large geographical areas. Success in spatial planning in the EU occurred with the development of a system of incentives capable of encouraging more cooperative and strategic relationships between local authorities and stakeholders. These relationships grew out of a pragmatic, bottom-up need to cooperate.

However, this is not to say that a fundamental change in governmental systems is necessary. Nadin (2002) and Salet et al. (2003b) both indicate that the best approach to spatial planning is to set up a framework that breaks down existing barriers to coordination and allows flexibility within the current planning system. Indeed, the change in approach to a broader vision proved effective in the EU when recognizing the particularities of the different geographic areas and then attempting to weave them into a higher order of social and economic collaboration and integration.

Experiences in the EU suggest that spatial planning success will require a governance framework that links national, regional, and local levels and is explicitly designed to build the capacity of the megaregion. This can only be done when participatory dialogue on many levels is a main component of the spatial planning process. These frameworks are ultimately derived from public sector focus and investment combined with a greater understanding of functional relationships derived from empirical study and wide ranging participation.

The global economy will give rise to new financial structures and new geographies. The evolution and transformation of our cities into megaregions and their critical role as economic centers in the global economy requires a better understanding of the role of global forces and how they affect people, places, and institutions. Additionally, we need to discern how this knowledge can be used to generate economic benefit, how to plan for it and how to measure it. Accountability and the ability to measure the outcome of certain investments and performance in megaregions are an intrinsic part of this new form of regionalism.

Updated: 5/14/2016
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