The National Institutes of Health (NIH) is offering a funding opportunity for pilot and feasibility studies aimed at substance use prevention trials, designated as R34 Clinical Trial Optional. This initiative focuses on developing new interventions to prevent the initiation and progression of substance use, as well as conducting services research that addresses the economics and quality of prevention strategies, particularly in underserved populations affected by challenges such as the opioid epidemic. Grants of up to $450,000 are available for projects lasting up to three years, with applications opening on January 16, 2024, and various deadlines for submission through 2026. Interested applicants can find more information and contact NIH Grants Information at grantsinfo@nih.gov or visit the announcement page at https://grants.nih.gov/grants/guide/pa-files/PAR-24-060.html.