Political thinkers have long sought to identify institutions that help produce good governance and this concern extends to recent research showing that electoral institutions influence governmental performance on a wide range of policy outcomes. In particular, countries with institutions such as proportional representation have been found to outperform countries with majoritarian institutions on a wide range of environmental, social health, and governmental performance indicators. This dissertation contributes to that line of thought by elaborating a framework that explains these results. I apply to the political arena insights from an interdisciplinary body of literature that identifies diverse perspectives as a factor enhancing the problem-solving capacity of small groups. I argue that electoral institutions influence the degree to which diverse perspectives are included in the policy-making process of a country and that this influence produces consequences important to a country's ability to deal with a wide range of policy problems.