This book expands the field of prison research by drawing on six months of unique, ethnographic research in Santa Monica prison, the largest women’s prison in Lima, Peru. Using feminist and decolonial perspectives, it explores power and the governance system and its implications on how the prison operates and the lived experiences of women prisoners and their interpersonal relationships. It reflects on the intersection of prison, imprisonment and gender from a Global South perspective and includes methodological reflections on how to research prisons in the Global South holistically. It fills a gap and engages with debates on governmentality and women’s agency within the penal context.