The far-reaching meaning of placebo and nocebo are often undervalued or ignored in clinical practice. Presently the term placebo is either used: (1) in the context of randomized controlled trials, (2) to describe a sham treatment in various nuances, (3) to describe effects often attributed to healers.This diverges from "no treatment" which has entirely different implications. Even less accepted is the term nocebo, which literally means "will harm". As placebo this term can be ambiguous and can appear in many concealed ways. Research in the past years has been based on experiments and elaborated studies and on imaging studies. This both placebo and nocebo also have an empirical and scientific background. Also, ethical aspects concern placebo and nocebo issues, in particular in regard to changing relations of the physician-patient relationship, which affects both terms. Based on this knowledge, increasingly physicians and patients are aware of these phenomena, and it will be important to raise awareness not only in physicians, but also the health care personal involved in the treatment of patients.