Young drivers are greatly over-represented in road traffic collisions (RTCs) worldwide. Interventions attempt to change driving-related behaviours to reduce injuries and deaths from RTCs. The current study evaluated the effectiveness of the well-established Fife Safe Drive Stay Alive (SDSA) practice-based intervention on determinants of driving behaviour using the health action process approach (HAPA) model. Adolescent participants (predominantly predrivers) attending the SDSA intervention from schools and colleges in Fife, Scotland, were invited to complete an evaluation at baseline and at 3 months exploring motivational determinants of driving behaviour (eg, risk perception). Intervention content was examined for behaviour change techniques (BCTs). Eighty-seven participants completed both baseline and follow-up evaluations. The motivational HAPA model variables predicted driving intentions. There was no significant overall effect of the SDSA intervention between baseline and 3-month follow-up. Seven negatively framed BCTs were used in the intervention. The effectiveness of SDSA is questioned; however, the study supports the use of the HAPA model in explaining driving intentions, and therefore, may usefully inform driving interventions.