Decentralization is an important and commonplace type of reform, yet our understanding of its effects remains limited. This paper documents the effects of the 2009-10 wave of district creation in Uganda, which increased the country's districts by 42 percent, using rich data on subdistrict units to assess the effects of district creation on a broad range of post-decentralization outcomes in a difference-in-differences framework. The effects of decentralization are concentrated in newly split off, rather than split from, districts and are heterogeneous across outcome types. Newly split-off districts have more per capita frontline workers but appear to have worse quality infrastructure and lower economic development. The study also presents suggestive evidence that administrative capacity decreases for newly formed districts post-split. These findings demonstrate the importance of considering a broad range of outcomes when thinking about decentralization