Economic change requiring a more highly skilled workforce prompted worldwide concern over high school drop out. Dropouts are young people who leave school early, often without attaining formal educational qualifications. Much previous research centred on at-risk students and a range of individual, social, family and school factors associated with drop out were identified. This case study of student drop out and retention at three girls’ state secondary schools over 2003 suggests that early leaving behaviour cannot be understood outside of the settings in which it occurs. Adopting an ecological perspective facilitated a deeper understanding of the complex interactions between the dropouts and their environment. From a narratives and numbers approach rich stories of early leaving emerged. Patterns of leaving were consistent with national trends: The lower decile school had the highest drop out rate, and dropouts were more likely to be Maori and Pasifika than European. Dropping out was shown to be a complicated and iterative process in which the influence of the environment is very important. Family and school relationships had a major impact but which had the greatest influence was inconclusive because there was a high level of interconnectedness between these proximal settings within the mesosystem and the bigger picture education and welfare systems. The extent of the contribution each level made to early leaving varied across individual stories, between schools and over time. Leaving school is an ecological transition that involves changing roles from high school pupil to that of tertiary student, mother, worker or benefit recipient. The students’ stories show drop out to be both an outcome, and an initiator, of developmental change. An important challenge for schools is not necessarily to reduce the number of early leavers but to establish effective transition programmes that assist students to become proactive in navigating the many transitions anticipated over their life course. The implementation of such school programmes needs to be supported by parallel changes in government policy.