On the occasion of the 25th anniversary of the journal Der Onkologe the state of psycho-oncology today is derived, balanced and discussed with respect to future challenges. Oncology and psycho-oncology have the same roots, which go back to Hippocrates in 400 B.C. (four humors theory). The modern era of psycho-oncology started in the early 1950s with the insight (of surgeons and psychoanalysts) that interdisciplinary cooperation is necessary for the well-being of cancer patients. After different detours and dead ends the present development is characterized by the effort to organize a nationwide psycho-oncological care, based on systematic indications. After 25 successful years the present focus is now on challenges in the fields of financing, integration, utilization, documentation and evaluation.