BackgroundEarly intervention alcohol and drug (AOD) programs for disadvantaged young people have the potential to substantially decrease the need for future intervention, however there is little research about how young people use these programs or the substance use and other outcomes of such programs. This paper uses data from an Australian AOD early intervention program, The Street Universities, to: describe young people’s participation; examine changes in substance use and wellbeing over 90 days; and assess which young people are most positively impactedMethodsData come from a prospective study of new attendees, measuring retention in and attendance patterns in an ‘engagement’ program focussed on arts and lifestyle activities (n = 95), and a routine service dataset collected from seven years of therapeutic intervention (n = 3,893), measuring substance dependence (SDS), psychological distress (K10) and quality of life (EQoL)ResultsAnalysis reveals that young people were retained in the program at high proportion (63% at six months) and more than half of these returned at a frequency of weekly or more often. Young people participating in the therapeutic component of the program reported significant improvements in all key wellbeing indicators with SDS, K10 and EQoL scores significantly improving (atp< .001). These improvements occurred rapidly, within the first 30 days, and were maintained over the 90 day study period. Moreover, young people with the highest SDS and K10 scores and lowest quality of life at baseline experienced the most positive changes.ConclusionAligning engagement program with therapeutic intervention can provide comprehensive support to disadvantaged young people, producing substantial improvements in AOD use, distress and wellbeing.