Objective: To determine what motivates smokers with mental illness to participate in a smoking cessation or reduction programme and to report their attendance and cessation rates. Method: A group programme was provided to assist smokers with mental illness to cease or reduce their use of tobacco. People who registered to address their tobacco use completed a questionnaire which included information about their mental health, tobacco use, and what they wanted to achieve by attending the programme. Results: A total of 1043 smokers living with mental illness contacted the programme and asked for help to address their tobacco use between 2000 and 2011. At the first contact they were smoking an average of 27.4 cigarettes per day and had been smoking for 23.8 years, and 87% said they wanted to quit tobacco and a further 10% wanted to smoke less: 85% said they were concerned about the effect that smoking tobacco was having on their health, 56% were concerned for financial reasons, and nearly half (47.6%) said that they were concerned about both their physical health and their financial situation. In Adelaide, 148 Tobacco Free programmes were provided by mental health services. Of those who attended at least one session and completed an evaluation at the end of the programme, 22.5% reported not smoking. Most remained motivated to continue to address their tobacco use and many registered for a further programme. Conclusions: Many smokers living with serious mental illness are concerned about the impact of tobacco use on their health and finances and are motivated to address it. Group treatment programmes specifically designed for these people can achieve good cessation rates and should be readily accessible to all smokers with mental illness. [ABSTRACT FROM AUTHOR]