This article reveals how the politics of federalism in the 1920s stifled the U.S. Children’s Bureau’s ability to collect national data on the workings of the Sheppard-Towner Act. The Bureau staff’s reliance on state administrators for data hindered their efforts to collect standardized national statistics on the states’ use of federal dollars. Ultimately, this barrier contributed to Sheppard-Towner’s defeat in 1929. Though the law was short-lived, the problems the Children’s Bureau encountered administering it provide insights into how federal matching grant programs began to shape federal and state relations before the New Deal. As this article shows, Bureau staff learned from their experience administering Sheppard-Towner that they needed to implement more stringent federal oversight over state-level accounting in their administration of Title V of the Social Security Act.