Study on changes in travel behaviour of students as result of the introduction of the "Student Public Transport Pass" (OV-Jaarkaart) on January 1st 1991. First wave 1990: possession of driving licence, car, bicycle, moped, public transport passes. Current type of education / location of r.'s educational institution / r.'s residence / residence of parents / description of trips, travels, made during a period of three weeks: place of departure, destinations, means of transport, use of public transport passes, reasons of trips. Wave 2 (1991) and 3 (1992) are partly replications of the first wave in 1990. Additional questions: changes in car ownership and place of residence / use of public transport during holidays in the Netherlands / changes in travel patterns. Background variables: basic characteristics/ household characteristics/ education/ consumption of durables