Mindfulness-based therapies are a recent development within the cognitive-behavioural tradition and an important element of the third wave cognitive behavioural therapy models. A number of these therapies could be considered to have mindfulness as a major component of the therapy. There has been a considerable growth of interest in these therapies with an accompanying increase in their evidence base. While a number of reviews have been conducted, these therapies were not comprehensively appraised. The most prominent of these therapies, mindfulness-based cognitive therapy, was developed to reduce relapse in recurrent depression. We conducted a meta-analysis which looked at therapies considered to have mindfulness as a major component. We investigated whether this group of therapies was effective in reducing current depressive symptomatology as measured by the Beck depression inventory (BDI). A total of 11 studies were included in the analysis. We found a significant mean reduction score in current depressive symptomatology, as measured by the BDI, of 8.73 points (95% confidence interval = 6.61, 10.86). We found evidence for the effectiveness of these major-component therapies in reducing levels of active depression. The robustness of these findings is discussed alongside the implications for research and practice within the context of the current literature.