AbstractThe use of plasma for healthcare can be dated back as far as the middle of the 19th century. Only the development of room temperature atmospheric pressure plasma sources in the past decade, however, has opened the new and fast growing interdisciplinary research field of plasma medicine. Three main topics can be distinguished: plasma treated implants, plasma decontamination, and plasmas in medical therapy. Understanding of the plasma sources and the plasma processes involved is still incomplete. With the aim of a more fundamental insight we investigate plasmas in a) functionalization of implants with antimicrobial as well as cell attachment enhancing surfaces b) atmospheric pressure plasmas (APPs) in inactivation of bacteria, decontamination of bottles and food products, as well as medical equipment and c) APPs in medical therapy and their effects on cell viability as a means to finding a plasma “dosage”. The possibilities of an application focused designing of plasma sources will be emphasized. On the example of feed gas humidity and its significant influence the importance of determining and controlling unobvious or hidden parameter is demonstrated (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)