During 2001-2002 a prototype, IMIS (Integrated Mobile Information System) was developed at BTH (Blekinge University of Technology) to demonstrate how mobile IT-systems can be used in healthcare. The prototype was based on the activity theory of Engeström. An ongoing project started in spring 2003. The purpose of the project is further development of IMIS with special focus in the diabetes healthcare. Participants in the project are scientists and students at BTH, ALMI Företagspartner, Blekinge FoU-enhet, Barndiabetesförbundet Blekinge, Blekinge Diabetesförening, Vårdcentralen Ronneby and Vårdcentralen Sölvesborg. The goal of IMIS is to develop a secure communication platform, which follows requirements from caretaker and caregiver as well as the Swedish laws regulating digital information and healthcare. The output of this master thesis is a requirement specification of information security for healthcare where IMIS has been used as a case study. The requirements specification follows the international standard SS-ISO/IEC 17799.