Psychotherapy is an extended and culturally welcomed practice in Argentina. Given the rapidly evolving psychotherapy techniques around the world, there is a unique opportunity to really sense how much benefit it can bring to the patients, specially those that pose the most challenge to clinicians. Effective practices with these patients can make a difference in mental health services and policies. This assessment can only be achieved with systematic case studies of interventions and effects in real time, in longitudinal designs, with real patients. This book is an attempt to contribute to the evidence practices in Psychotherapy, and is intended to encourage clinicians to sum their work in a networking fashion. In this book, both psychotherapists, Marian and Elena, describe thoroughly how the treatment process evolved, assessing every phase and treatment outcome with quantitative and qualitative measures in each of the cases. The case conceptualization and specific interventions are also described in detail. We hope that this work will help clinicians in their daily struggle to help patients, and encourage more clinicians to sum up to the Evidence Based Psychotherapy movement.