Markets are increasingly used by governments to deliver social services, underpinned by the belief that they can drive efficiency and quality. These ‘quasi‐markets’ require on‐going management to ensure they meet policy goals, and address issues of market inequity. This has seen debates emerge around ‘market stewardship’ and ‘market shaping’ that centre on how best to manage markets towards optimal policy outcomes. At present there is a significant gap in both literature and practice with regard to what types of actions are most effective for market stewardship. In this article we outline a framework that helps diagnose different quasi‐market problems. We delineate two dimensions of public service quasi‐markets – sufficiency and diversity – using the example of a disability personalisation market to show how this framework can unpack different types of quasi‐market states. Lastly, we outline the types of interventions that might be adopted to help deal with ineffective quasi‐markets.