At present the treatment of choice for most opiate dependent persons in Europe is long term substitute prescribing. Given the poor evidence base and also the increased risk of overdose, following a period of abstinence, many clinicians opt to dissuade opiate dependent persons from detoxifying. Opiate detoxification is not an effective stand-alone treatment for opiate dependence but is nevertheless an essential step to recovery. However, there is no medium or long-term outcome data examining these issues for this population of patients in Ireland. The aim of the proposed study is to follow the treatment progress of a baseline sample of opiate dependent patients post detoxification. The purpose is to examine abstinence rates at 3, 6 and 9 month follow up and investigate the relationship between rehabilitation pathways and observed outcomes across each of the three rehabilitation pathways i.e. inpatient rehabilitation programmes, outpatient rehabilitation programmes or simply return to the community without any formal aftercare. The study sets out to comprehensively uncover factors that influence and predict rates of relapse to regular opiate use following residential detoxification. There are three arms in the current study arm 1 is a Neuro-imaging arm (patients are given a base-line Functional Magnetic Image (fMRI) scan, arm 2 is Quantitative arm patients are given a battery of validated outcome measures at base-line and repeated at 3, 6, & 9 months post-detoxification) and a Qualitative arm 2, a sub-sample of patients are interviewed at base-line and repeated at 3, 6, & 9 months post-detoxification). The projected completion of this project is March 2014.