Background: Collaborative Care is an evidence-based approach to the management of depression within primary care services recommended within NICE Guidance. However, uptake within the UK has been limited. This review aims to investigate the barriers and facilitators to implementing Collaborative Care. Methods: A systematic review of the literature was undertaken to uncover what barriers and facilitators have been reported by previous research into Collaborative Care for depression in primary care. Results: The review identified barriers and facilitators to successful implementation of Collaborative Care for depression in 18 studies across a range of settings. A framework analysis was applied using the Collaborative Care definition. The most commonly reported barriers related to the multi-professional approach, such as staff and organisational attitudes to integration, and poor inter-professional communication. Facilitators to successful implementation particularly focussed on improving inter-professional communication through standardised care pathways and case managers with clear role boundaries and key underpinning personal qualities. Limitations: Not all papers were independent title and abstract screened by multiple reviewers thus limiting the reliability of the selected studies. There are many different frameworks for assessing the quality of qualitative research and little consensus as to which is most appropriate in what circumstances. The use of a quality threshold led to the exclusion of six papers that could have included further information on barriers and facilitators. Conclusions: Although the evidence base for Collaborative Care is strong, and the population within primary care with depression is large, the preferred way to implement the approach has not been identified.