OBJECTIVE: Evaluate the impact of an integrated brief intervention to assist antenatal staff in addressing smoking with pregnant women. DESIGN: Three studies were conducted: (a) antenatal staff surveys pre- and post-training to deliver the brief intervention; (b) retrospective audit of pregnancy records; (c) post-intervention follow-up interviews with a cohort of pregnant women who smoked at baseline. SETTING: South Australia. SAMPLE: (a) Antenatal health professionals at two major birthing hospitals (n = 117 pre-survey and n = 62 post-survey); (b) 1,024 pregnancy records; (c) follow-up interviews with women at one month (n = 58), 6 months (n = 40) and 12 months (n = 31) post-intervention. METHODS: (a) Staff surveys about current practice prior to training (via written questionnaire) and 12 months post-training (by telephone); (b) pregnancy record audit for presence and use of the Smoke-Free Assessment & Intervention Form (SFA&IF) conducted at 12 months; (c) telephone surveys assessing smoking behavior. MAIN OUTCOME MEASURES: Staff practice change and compliance with the intervention. Cessation rates among pregnant women. RESULTS: At 12 months, 89% of staff reported that the intervention integrated well into their work; The SFA&IF was physically present in 80% of pregnancy records and 89% had been completed. Over 65% of current smokers were offered advice about the benefits of quitting; quit rates were highest at 6 months (18, 13% conservative estimate), but women tended to relapse after the birth of their baby. CONCLUSIONS: The intervention was well-received and staff compliance was high. Quit rates exceeded spontaneous quit rates in the community. This project has been expanded nationally.