Transparency has been hailed as the key to better governance, yet political actors have many reasons to resist transparency. This article studies one prominent transparency policy, Freedom of Information (FOI) laws, which have been passed by over 80 countries. By institutionalizing transparency, FOI laws increase the costs for political actors to use public office - and public information - for private gain. Why have so many states passed FOI laws despite this? I argue that, in competitive political environments, FOI laws can create benefits for political actors as well as costs. Uncertainty over future control creates incentives for incumbents to pass FOI laws in order to ensure their own future access to government information and to credibly commit to future transparency. Event-history-model results show that FOI law passage is more likely when opposition parties pose more credible challenges to incumbents and when recent turnover in executive office has been frequent.