There is increasing interest in research-based education in the Western World as it is assumed to strengthen school improvementcapacity. Previous research shows that school principals play a pivotal role in realising such vision. The aim of this article is toexplore the influence of principals on research-based education in their local municipal adult education (MAE) institutions. Thestudy is informed by the theory of practice architecture. Data rely on 10 interviews with the principals of eight local MAE insti-tutions. The study draws attention to how inherent contradictions in the national education system may hinder the policy am-bitions related to research-based adult education. These contradictions not only affect principals' leadership practices in variousways, but also their ability to ensure research-based adult education. It is suggested that understanding the practice architectureis fundamental to enhancing leadership practice, which is also exemplified.