Despite shared history and a common ambition to comply with European standards, post-Soviet countries differ in the way in which they reform prisons. By investigating two most-similar cases of policy transfer from Norway – the establishment of the Olaine Drug Centre in Latvia and the Pravieniškės Drug Unit in Lithuania – this article explains why outcomes diverge and how Western-European carceral individualism clashes with path-dependent carceral collectivism. Where leadership is unstable, with limited powers, the informal legacies are strong, and policy-transfer strategy is fragmented, as in Lithuania, the outcome is likely to be non-transformative. Where, on the contrary, leadership is stable, enjoying larger discretionary powers and the intervention strategy is holistic, as in Latvia, the import of foreign institutional models is likely to be successful.