As humans, but also as researchers and clinicians, we can learn a lot from our failures. The issue of failures in psychotherapeutic treatments is extremely important, as from them we can infer the signs that precede them, and the strategies to deal with them. In psychotherapy we are also aware of the important fact that the amount of unwanted effects is very similar to fields such as pharmacotherapy, and the number of patients reporting unwanted effects of psychotherapy is between 3 and 15% of cases (Berk and Parker, 2009). In 2012, a meta-analytic study by Swift and Greenberg (2012)suggested that approximately one in every five clients still chooses to end treatment prior to its completion. Similarly, Lambert (2013) has demonstrated that 5 to 10% of patients deteriorate in therapy, and 35 to 40% of participants in clinical trials do not improve. This Research Topic asks how we can address this situation.