A report is given on the development of a system for the distribution of encrypted digital contents via freely accessible distribution media. To be able to use this information, the key needed for decryption has to be ordered from a key management system. The distribution of the keys required for decryption is restricted whereas the distribution of the encrypted contents is not. The key is sent to the customer only if sufficient payment has been authorised. The system described in this paper is designed (i) to be independent of the method used for distribution of the encrypted contents, (ii) to support many different payment systems, (iii) to support casual customers (nonregistered users), (iv) to avoid complicated software setup, contract conclusion and registration processes, and (v) to support re-selling of other manufacturer's contents in simple way without extra contracts. In addition, (vi) the system can be easily adapted to support workflow management in a business-to-business environment.