Measuring government effectiveness is essential to ensuring accountability, as is an informed public that is willing and able to hold elected officials and policy-makers accountable. There are various forms of measurement, including against prior experience or compared to some ideal. In Yardstick Competition among Governments, Pierre Salmon argues that a more effective and insightful approach is to use common measures across a variety of countries, state, or other relevant political and economic districts. This facilitates and enables citizens comparing policy outputs in their own jurisdictions with those of others. An advantage of this approach is that it reduces information asymmetries between citizens and public officials, decreasing the costs of monitoring by the former of the latter -along the lines of principal-agent theory. These comparisons can have an effect on citizens' support to incumbents and, as a consequence, also on governments' decisions. By increasing transparency, comparisons by common yardsticks can decrease the influence of interest groups and increase the focus on broader concerns, whether economic growth or others. Salmon takes up complicating factors such as federalism and other forms of multi-level governance, where responsibility can become difficult to disentangle and accountability a challenge. Salmon also highlights the importance of publics with heterogeneous preferences, including variations in how voters interpret their roles, functions, or tasks. This results in the coexistence within the same electorate of different types of voting behavior, not all of them forward-looking. In turn, when incumbents face such heterogeneity, they can treat the response to their decisions as an aggregate non-strategic relation between comparative performance and expected electoral support.Combining theoretical, methodological, and empirical research, Salmon demonstrates how yardstick competition among governments, a consequence of the possibility that citizens look across borders, is a very significant, systemic dimension of governance both at the local and at the national levels.