Using administrative sources in the history of education and childhood involves a range of methodological and ethical considerations. This article discusses these problems, as well as the role of archives and archival policies in preserving history and shaping our understanding of past childhoods. Using Finnish child welfare archives from the post-war period (1945-1970) as an example, the article shows how the institutional gaze of administrative archives, together with various screening practices, has limited the research possibilities. Nevertheless, administrative records do offer important perspectives on the lives of marginalised children and young people that cannot be reached through other sources. The article closes with a critical discussion on the tightening research ethical regulations, and argues for the historian's right to access original sources. Researchers' rights should be ensured in forthcoming archival practices and legislation, and contested research topics should not be avoided because of research ethical uneasiness.