In New Zealand few teenagers cycle to school and the percentage of teenagers cycling to school has dropped greatly since the 1990s. This research investigates why more teenagers do not cycle to school in Christchurch, New Zealand. Specifically it aims to identify: 1) the nature of teenagers’cycling behaviour in Christchurch; 2) the key barriers to teenagers cycling to school; and 3) whether theories of behaviour change are useful in predicting cycling to school by teenagers. The research uses the results of interviews with staff, and focus groups and surveys with students at seven high schools in Christchurch, New Zealand. Focus groups with students at a British international high school in Voorschoten in the Hague Region of the Netherlands also enabled comparison of whether teenagers who had grown up in places where few teenagers cycled to school (such as the UK) were influenced by different factors when they moved to places like the Netherlands where almost everyone cycles. Perceived social pressure by friends had the greatest influence over whether or not students intended to cycle to school, closely followed by perceived social pressure by parents. Both of these factors are classified in the literature as ‘subjective norms’. Analysis also showed additional factors concerning the individual and the behavioural setting also influenced teenagers’ decisions to cycle to school. The comparative study showed students who had grown up in places where few people cycled changed their behaviour and cycled to school when they moved to places where lots of people cycled, due to the influence of norms. Teenagers who cycled the least were girls, older students and students from lower socio-economic areas. Therefore, to be effective, any programmes to increase cycling to school would need to be targeted in recognition of the differences between these groups. After all, a thirteen year-old teenage boy is quite different to an eighteen year-old girl. To increase the number of teenagers cycling to school in Christchurch, the most important thing required is change to societal attitudes and norms in favour of cycling. In addition, a range of practical initiatives such as improved infrastructure and cycle skills programmes are recommended. Overall what is required is change at multiple levels, targeting individuals, social environments, physical environments, and policies. Change will never be achieved by tinkering around the edges.