This study aimed to analyse the rates and length of time to relapse and/or recurrence of depression in individuals who attended either Group CBT or Group Information and Support in an adult secondary mental health setting in Ireland. The present study centred on the analysis of previously collected data from groups running between 2005 and 2010 and on the retrospective file review. It formed part of a larger scale research study conducted by the Principal Clinical Psychologist evaluating the effectiveness of CBT for depression and bipolar disorder. The study was quantitative in nature and incorporated qualitative elements (i.e. Clients' and Practitioners' description of the severity of the depressive episodes) which were converted into quantifiable categories. Participants comprised of two groups: Treatment I (Group CBT) including participants who attended 8 or 12 sessions of manualised Group CBT and a comparison sample: Treatment II (Group Information and Support) comprised of participants who attended 12 sessions of group information and support. Based on survival analysis, no significant difference was found in effectiveness for Group CBT and Group Information and Support in preventing and/or decreasing the number and the length of time to relapse and/or recurrence of depression in this client group. Findings, clinical implications, methodological limitations and future research directions were also discussed.