Public participation in administrative decision making has been widely advocated by both theorists and practitioners of public administration. Despite the importance of citizen engagement, we know little about its impact on the performance of government agencies. Is participation only normatively desirable or does it have some practical value attached to it? We draw on data from U.S. state transportation agencies to test the relevance of two theoretical perspectives about the effect of public participation on organizational performance. The traditional perspective holds that there is a trade-off between democratic and administrative decision making. A competing perspective suggests that citizen input provides administrators with valuable site-specific information and contributes to more efficient and effective public programs. We find strong support for the latter perspective. Our results show that there is not necessarily a trade-off between the values of democracy and bureaucracy, with clear implications for the theory and practice of democratic governance.