Purpose: Risky alcohol and other drug (AOD) use is ubiquitous in some workplace cultures, and is associated with considerable risks to health, safety and productivity. A workplace drug and alcohol first aid program was developed to support supervisors and managers to recognize and respond appropriately to AOD problems, increase knowledge of AOD and reduce the stigma associated with AOD. The purpose of this paper is to undertake an evaluation to assess the program’s efficacy. Design/methodology/approach: A self-report survey was administered to program participants before (T1), immediately after (T2) and three months following program completion (T3). Changes in alcohol/drug-related knowledge, role adequacy, motivation and personal views were examined using repeated measures ANOVA. Findings: A total of 109 participants took part in the program, with only 26 completing scores at all three time points. Mean scores increased significantly (p<0.05) between T1 and T2 for knowledge (12.7–16.0), role adequacy (11.8–17.4), motivation (9.7–10.4) and personal views (9.0–9.6). Significant improvements were maintained at T3 for knowledge (15.1) and role adequacy (17.3). Practical implications: Drug and alcohol first aid programs offer a potentially valuable initiative to improve the knowledge, skills and understanding of managers and supervisors in tackling workplace AOD risks, associated stigma and improving help seeking. Originality/value: Workplace programs for managers can facilitate organization-wide responses to the reduction of AOD-related problems, increase implementation of appropriate policy and interventions, minimize associated harms and stigma and reduce negative imposts on productivity and profit.