Governments are resource and bandwidth constrained, and hence need to prioritize productivity-enhancing policies. To do so requires information on the nature and magnitude of market failures on the one hand, and government's capacity to redress them successfully on the other. The paper reviews perspectives on vertical (sectoral) and horizontal (factor markets, cluster) policies with an eye to both criteria. It first argues that the case for either cannot be made on the basis of the likelihood of successful implementation: for instance, educational and picking the winner types of policies both run the risks of capture and incompetent execution. However, the profession has been able to establish more convincing market failures for horizontal policies than for vertical policies. Most of the recent approaches to identifying failures around particular goods, the paper argues, are of limited help. Hence, for a given difficulty of execution, the former are generally to be preferred. A second critical message is that improving the quality of governance in terms of collecting information, coordination ability, and defending against capture is critical to successful implementation of productivity policies and should be central on the policy agenda.