The main aim of the book is to assess and explain the extent to which political parties across Europe as a whole succeed in representing diverse voters. We note two important features of the European political landscape that complicate the task of assessing party representation and that require its reassessment. First, the emergence of new democracies in post-Communist Central and Eastern Europe point to the possibility that representation is not only differentially achieved in West and East but may also be attained by different mechanisms. Second, parties in both West and East must now seek to represent voters that are increasingly diverse, specifically between partisan and independent supporters. We refer to the challenges of representation of diverse voters as the strain of representation’. The evidential basis for the empirical analysis are expert surveys that were conducted in 24 European countries on party positions that were merged with other available data on voters, party characteristics, and country conditions. The results point to both the representational capacities of parties in West and East and to the strain that parties face in representing diverse voters.