Background:Public health programs are charged with implementing evidence-based interventions to support public health improvement, however, to achieve long term population based benefit these interventions must be sustained. Empirical evidence suggests that program sustainability can be improved through training and technical assistance, but few resources are available to support public health programs in building capacity for sustainability.Methods:This study sought to build capacity for sustainability among state tobacco control programs through a multiyear, group-randomized trial that developed, tested, and evaluated a novelProgram Sustainability Action Planning Model and Training Curricula. Using Kolb’s experiential learning theory, we developed this action-oriented training model to address the program-related domains proven to impact capacity for sustainability as outlined in the Program Sustainability Framework. We evaluated the intervention using a longitudinal mixed-effects model using Program Sustainability Assessment (PSAT) scores from three time points. The main predictors in our model included group (control vs intervention) and type of dosage (active and passive). Covariates included state level American Lung Association score (proxy for tobacco control policy environment) and percent of CDC-recommended funding (proxy for program resources).Results:Twenty-three of the 24 state tobacco control programs were included in the analyses: 11 received the training intervention and 12 were control. Results of the longitudinal mixed-effects linear regression model, where the annual PSAT score was the outcome, showed that states in the intervention condition reported significantly higher PSAT scores. The effects for CDC-recommended funding and American Lung Association smoke-free scores (proxy for policy environment) were small but statistically significant.Conclusion:This study found that theProgram Sustainability Action Planning Model and Training Curriculawas effective in building capacity for sustainability. The training was most beneficial for programs that had made less policy progress than others, implying that tailored training may be most appropriate for programs possibly struggling to make progress. Finally, while funding had a small, statistically significant effect in our model, it virtually made no difference for the average program in our study. This suggests that other factors may be more or equally important as the level of funding a program receives.Trial registration:NCT03598114, Registered on July 26, 2018 (clnicaltrials.gov/NCT03598114)