Abstract
The shift from ownership to service use, often promoted in concepts of sustainability, has recently become available in private vehicle mobility. Currently 38,000 people in a number of European cities are participating. This example is used here, to analyse the characteristics of people sharing one `material' product as well as to investigate which service they actually render. Different views on the latter imply different evaluations of the size of the market potential and different conclusion on the effectiveness of various policy instruments. When service use is a separate lifestyle, policy instruments have to ultimate foster it directly, rather than changing economic costs at the margin only. (A)