Trust in political institutions and in other people is hypothesized by cultural theories to be essential for making democracieswork. Trust is equated with diffuse support and linked to the stability and effective functioning of democratic regimes. Institutional theories, in contrast, question the importance of trust for democratic support and emphasize institutional performance instead. A structural equation model using New Russia Barometer survey data tests cultural and institutional theories of regime support. The results confirm cultural arguments that institutional trust encourages political involvement and contributes to public support for democratic ideals, whereas they contradict the hypothesis that trust is critical for political support. Much stronger support exists for institutional theory’s claims about the importance of economic and political performance. Cultural influences, however, appear somewhat larger than institutional theories allow and may become larger still during the longer term, suggesting the need to integrate cultural and institutional theories.