Consociational theory suggests that power–sharing institutions have many important consequences, not least that they are most likely to facilitate accommodation and cooperation among leadership elites, making them most suitable for states struggling to achieve stable democracy and good governance in divided societies. This study compares a broad cross–section of countries worldwide, including many multiethnic states, to investigate the impact of formal power–sharing institutions (PR electoral systems and federalism) on several indicators of democratic stability and good governance. The research demonstrates three main findings: (i) worldwide, power–sharing constitutions combining PR and federalism remain relatively rare (only 13 out of 191 states); (ii) federalism was found to be unrelated to any of the indicators of good governance under comparison; and (iii) PR electoral systems, however, were positively related to some indicators of good governance, both worldwide and in multiethnic states. This provides strictly limited support for the larger claims made by consociational theory. Nevertheless, the implications for policymakers suggest that investing in basic human development is a consistently more reliable route to achieve stable democracy and good governance than constitutional design alone.