ABSTRACT Background Prior systematic reviews and research have suggested that certain organizational characteristics and training methods may support the sustainability of new practices, yet these factors have not been adequately studied in behavioral health. Objective The objective of this study was to test the indirect effects of training design (e.g. training condition and consultation call attendance) on clinician-reported sustainability through post-training organizational resources, training exposure and utilization, and organizational climate. Method Fifty licensed outpatient clinics, including 100 clinicians, 50 supervisors, and 50 administrators were randomized to one of three training conditions: 1) Learning Collaborative (LC), 2) Cascading Model (CM), or 3) Distance Education (DE). All were trained to provide Parent Child Interaction Therapy (PCIT). Data to assess training and implementation outcomes were collected at 4 time points coinciding with the training period: baseline, 6- (mid), 12- (post), and 24-months (1-year follow-up). Multi-level path analysis was utilized to examine the role of organizational barriers and training approaches on the sustainability of PCIT (caseload, protocol use, number of families seen). Results Clinician-reported resources, training exposure and utilization, and organizational climate varied among study conditions, with the most favorable conditions reported in the CM condition and the least favorable conditions reported in the LC condition. The CM condition was associated with greater PCIT caseload, more families served by the PCIT program, and less use of the full PCIT protocol as compared to the DE condition, while the LC condition was associated with fewer families served and more use of the full PCIT protocol. Conclusions Organizational factors such as available resources, organizational climate, and training exposure and utilization indirectly influence the effect of training approach and consultation on PCIT sustainability two years after baseline and vary based on condition. A possible mechanism of the cascading training model on sustainability, through increased organizational resources, was also identified.