This chapter presents the findings of a prospective, randomized comparative outcome study of the effect of time-limited individual child psychotherapy and systemic family therapy on severely depressed young people funded by a BIOMED ERC grant. The current trend for combining the use of quantitative and qualitative approaches (Midgley 2006) addresses the need both to provide evidence of effectiveness in terms that are accepted in the wider professional community of non-psychoanalytic workers and to examine the process of treatment in a manner that is meaningful to psychotherapists and may shed light on what factors contribute to improvement.