[en] With experience from many years of data collection in the Man - Machine and Virtual Reality Laboratories at the OECD Halden Reactor Project, an evident need for more efficient handling of questionnaire data was documented. A working prototype on-line system for World Wide Web (www) questionnaire generation and data collection was developed and tested. This paper discusses the use of www-based data collection and the need for system functionality in experiments and surveys. Insights from the development of the system are reported together with experiences using such tools in simulation and realistic field experimentation. (Author)