This volume is a common product of an international group of scholars interested in decision-making and sentencing in the context of the criminal justice system who have worked together in the Working Group on Decision-Making and Supervision of the COST Action IS1106 on Offender Supervision in Europe from 2012–2016. Already in an earlier common publication in the first book deriving from this Action (McNeill and Beyens 2013), we concluded that breach processes following non-compliance with community sanctions and measures was an under-researched topic in the literature on Offender Supervision, although more has been done on recall to prison than on revocation of community sanctions. A comparison of the legal procedures of these countries involved in the COST Action showed that extreme variations exist in the procedures, the extent of discretion and the outcomes in relation to breach and recall (Boone and Herzog-Evans 2013). Since that time we have continued working on this topic, both for methodological and for material reasons. Having concluded that this topic deserved more academic attention we decided to focus on breach processes when tasked with developing innovative comparative methodologies during the last two years of our COST Action.