In terms of integrative oncology, complementary medicine is used additionally to conventional mainstream medicine, while alternative medicine is used instead of established medical treatment. The alternative treatment of breast cancer leads to an increased mortality risk and should not be recommended. Sound information about complementary medicine can be obtained through the Society for Integrative Oncology (SIO) and the Working Group in Oncology (AGO) guidelines as well as the website of the Memorial Sloan Kettering Cancer Center. In complementary medicine especially methods from mind-body medicine, e.g. endurance and power training, mindfulness-based stress reduction (MBSR) and yoga are effective to improve insomnia, anxiety/stress and fatigue. Furthermore, acupuncture and acupressure can also be considered to treat fatigue whereas acetyl-L-carnitine is not recommended. Because of the prognostic relevance of stress and insomnia in cancer patients, these symptoms should be detected and treated at an early stage.