WP4 reviews measures and policies aiming to wrestle with urban sprawl,analyses case studies in Europe and in the USA, an investigates the institutional and organisational barriers to the implementation of these policies. Another goal of the review is to support the selection of measures that will be simulated and assessed in WP5.

The review of policy measures is based on 3 sources:

• Task 1: bibliographical review of policies: review of measures and policies, on the basis of, research studies, scientific literature and urban planning literature, etc;
  
  

• Task 2: review of measures planned or implemented in the case cities and in other selected cities in Europe and in the US;
  
  

• Task 2: interviews of urban and transport planners in the United States working within local authorities: many American cities have been subject to urban sprawl for a longer time that those in Europe. American urban planners have therefore designed and already tested numerous policies aiming to tackle urban sprawl; whatever the dissimilarities between American and European cities, the US experience is of great value to European urban planners;

The review includes the description of various policy measures implemented in the case cities, the expected or observed results where such results are available, an analysis of the actors and financial mechanisms involved.
WP4 also includes a review of institutional barriers to implementation processes (Task 3). In many cases, institutional players might constitute a barrier to the implementation of policies. Sometimes, they might be in competition against each other to capture local development processes. Often, the problem is in relation with the distribution of competences: different institutional players have competences on different planning fields, such as transport or land-use or the environment. This also highlights the need for new institutional tools to tackle urban sprawl.