The process of judicial control over institutions is often described as growing socio-legal trend which impacts the development of modern societies. This is particularly the case for prisons and other penal institutions, as international bodies and the courts have tried to influence prison policies since the 1960s. This book addresses this dynamic situation by focusing on European monitoring as a major influence on penal and prison policies within, between and across nation states. Bringing together experts from around Europe, this book actively contributes to debates and analysis within penal and prison policy studies by shedding lights on the impacts of monitoring, and demonstrates how the study of penal and prison reform in different European countries can contribute to building a clearer and more precise picture of European legal systems.This book will be of interest to researchers in the fields of prisons, penology and punishment, as well as policymakers and professionals working for national Ministries of Justice and for prison department and national human rights institutions, as well as those working for INGOs and NGOs.