Depressive and adjustment disorders are highly prevalent in patients with physical diseases and are associated with poorer quality of life, increased morbidity and mortality, as well as higher healthcare costs. Access to mental health care holds strong importance for these patients, although waiting times for outpatient individual psychotherapy in Germany are often long. Attending an intervention while waiting for individual therapy could improve this problem. For this purpose, we developed an eight-session cognitive behavioral group therapy (STEpS) and tested its efficacy in a randomized controlled trial.