This concept note presents political economy system maps (PESMs). PESMs are a conceptual and visual tool to help policy-makers think about the problems affecting the production and delivery of public goods and services from the point of view of the system’s political organization, as well as possible interventions to solve those problems. These maps help to problem-solve by transforming information about a public good and services production and delivery into a set of simple strategic insights about the underlying political landscape (actors, flows and processes) on which the system is based upon. In so doing, these maps can help understand better the incentives and expectations at play in a public policy system and to manage reform processes.We use the case of transparency and accountability reforms to illustrate our point.