A very flexible software system called «Electronic Warden» has been developed. It is based on a «client/server» architecture. It controls and manages the access right of the complex and heterogeneous data computer system at St Luc Hospital in Brussels. The electronic warden is independent of the other software applications of the hospital and is connected to them through API'S. The physical access is managed with the use of smart card and allows the electronic signature. The management of the users and their accesses to the data is run in a centralised or a decentralised way which allows a lot of flexibility.