There is always a need for new measures of public accountability and integrity, not so much because current systems are lacking, but because new challenges constantly arise. One such challenge is emerging as parliamentary systems within Westminster-influenced jurisdictions are becoming more accustomed to minority parties and/or independents playing a significant role in government. This is particularly potent in the current Australian context where a minority parliament has resulted in a situation where the changing vote of any parliamentarian could change the outcome of legislation. This situation raises new questions and presents new opportunities for the development of enhanced measures to support ethical action and decision-making for all parliamentarians. More specifically, the anticipated creation of an Australian Commissioner of Parliamentary Integrity, with a brief to provide advice on ethical issues for parliamentarians, provides such an opportunity. This article draws on recent literature to put forward an expanded model of 'parliamentary integrity', as well as acknowledging the need for greater practical utility of concepts in this field by exploring a range of challenges that face independents and single-member parties. It suggests that the new Commissioner's role might be grounded in a notion of parliamentary integrity as the service of the public good, rather than the simple avoidance of coercion, corruption or crime. In doing so, the article identifies not only an opportunity to respond to the current political landscape in Australia but also to set a new standard for integrity and accountability in Westminster systems.