Background: This study applied the theory of planned behaviour (TPB) in an attempt to predict longitudinal growth of career exploratory behaviour in school pupils. The importance of information for making considered career decisions is indicated in theories of career development and choice, career education programmes, and concepts of career maturity. Aims: The study aimed to initially model individual and group levels of career exploratory behaviour and then to identify psychological variables that predicted such behaviour. Sample. Longitudinal data from a sample of 325 adolescents (mean age 16.4 years, SD = 0.77, 45% were male) was collected at three points in time. Method: A latent growth curve model was specified to account for initial status and subsequent linear growth of career exploratory behaviour. Variables representing the TPB were included in the model to explain the variation in the intercept and slope factors. Results: The latent growth curve model was found to be an acceptable description of the data, and indicated that there was significant individual variability in terms of the intercept and slope factors. Behavioural intention was found to be a significant predictor of the intercept factor, but not of the slope factor. Conclusions.: It was concluded that the TPB remains a useful theoretical framework from which to explain career information-seeking behaviour.