Background: It is recognized that a significant proportion of people with depression are prone to relapse, even after successful treatment, and that self-management interventions should be developed and provided. There is evidence that implementation intentions (IMPS) can be successfully applied to health-related behaviours but their application to self-management of mental health problems has been limited. Aims: This paper describes the design and initial evaluation of a Self-Management After Therapy (SMArT) intervention, which incorporated IMPS and followed psychological therapy for depression. We sought to assess the feasibility and acceptability of SMArT. Method: The SMArT intervention was designed with reference to the MRC guidance on developing and evaluating complex interventions and co-designed with and implemented in a UK Improving Access to Psychological Therapies (IAPT) service. Eleven patients who were in remission following treatment for depression received the SMArT intervention, provided by Psychological Wellbeing Practitioners (PWPs). The evaluation used routine IAPT outcome measures at each session, feedback from patients and PWPs, and analysis of the type of IMPS identified and their fidelity with the model. Six patients provided brief feedback about the intervention to an independent researcher. Results: Feedback from patients and PWPs suggested that the intervention was feasible, acceptable and could potentially help patients to stay well after therapy. Patients confirmed the value of setting their own goals in the form of IMPS, receiving support from PWPs and in some cases from partners, friends and family members. Conclusions: Implementation intentions are a promising approach to support the self-management of depression.