This study investigates the relationships between unemployment following school leaving and psychosocial adjustment problems (mental health, substance use, crime, suicidal behaviours and teenage pregnancy) in a birth cohort of over 1000 New Zealand born young people. The data were gathered during the course of the Christchurch Health and Development Study (CHDS). The CHDS is a longitudinal study of a birth cohort of 1265 children born in the Christchurch (NZ) urban region who have been studied from birth to age 21. Data were gathered by personal interview on: (a) exposure to unemployment and (b) personal adjustment over the period from age 16 to age 21. Measures of personal adjustment included mental health (depression, anxiety), substance use, crime, suicidal behaviours and (for females) teenage pregnancy. Data were analysed using a fixed effects regression model that took into account both observed and non-observed sources of confounding and the possibility of reverse causal associations between personal adjustment and unemployment. Before adjustment for confounding and reverse causality there were significant (p < 0.001) associations between exposure to unemployment and measures of mental health, substance use, crime, suicidal behaviours and teenage pregnancy. Adjustment for confounding factors and reverse causality reduced these associations quite substantially and after control for sources of confounding a number of associations became nonsignificant. Nonetheless, after such control, exposure to unemployment remained significantly (p < 0.05) associated with suicidal ideation, substance abuse and criminal behaviours. It is concluded that, in part, the associations between unemployment and personal adjustment are spurious and reflect the presence of confounding factors that are related to both unemployment and adjustment. Nonetheless, the findings suggest that exposure to unemployment may be associated with increased risks of suicidal thoughts, crime and substance use.