This study measured substance use disorder clinicians' perceptions regarding the implementation extensiveness of the Office of Alcohol and Substance Abuse Services (OASAS) tobacco-free regulation, passed in New York State in July of 2008, at three time-points and across organizations with varying characteristics. Repeated cross-sectional data were collected from clinicians approximately 4months pre-regulation (time 0, n=362), 10–12months post-regulation (time 1, n=462), and 20–24months post-regulation (time 2, n=509). Clinician perceptions of implementation extensiveness (number of required policies in effect), use of tobacco cessation-related intake procedures, and use of guideline recommended counseling for treating tobacco dependence are significantly greater at time 1 and time 2 compared to time 0. Additionally, differences are found in perceived implementation extensiveness based on hospital-based status, profit status, and level of care offered, although the pattern of effects differed some over the three time-points under investigation.