Background: Research on root cause analysis (RCA), a pivotal component of many patient safety improvement programmes, is limited. Objective: To study a cohort of health professionals who conducted RCAs after completing the NSW Safety Improvement Program (SIP). Hypothesis: Participants in RCAs would: (1) differ in demographic profile from non-participants, (2) encounter problems conducting RCAs as a result of insufficient system support, (3) encounter more problems if they had conducted fewer RCAs and (4) have positive attitudes regarding RCA and safety. Design, setting and participants: Anonymous questionnaire survey of 252 health professionals, drawn from a larger sample, who attended 2-day SIP courses across New South Wales, Australia. Outcome measures: Demographic variables, experiences conducting RCAs, attitudes and safely skills acquired. Results: No demographic variables differentiated RCA participants from non-participants. The difficulties experienced while conducting RCAs were lack of time (75.0%), resources (45.0%) and feedback (38.3%), and difficulties with colleagues (44.5%), RCA teams (34.2%), other professions (26.9%) and management (16.7%). Respondents reported benefits from RCAs, including improved patient safety (87.9%) and communication about patient care (79.8%). SIP courses had given participants skills to conduct RCAs (92.8%) and improve their safety practices (79.6%). Benefits from the SIP were thought to justify the investment by New South Wales Health (74.6%) and committing staff resources (72.6%). Most (84.8%) of the participants wanted additional RCA training. Conclusions: RCA participants reported improved skills and commitment to safety, but greater support from the workplace and health system are necessary to maintain momentum.