Boards are central to the system of nonprofit accountability, so understanding how boards function and identifying strategies for strengthening them remains key to enhancing nonprofit accountability. This paper examines board functioning in relation to both legal and broader conceptions of accountability, and empirical evidence from over 5,100 nonprofits in the Urban Institute National Survey of Nonprofit Governance. After discussing areas of board weakness, the paper considers various approaches to improving boards, including regulation, self-regulation, policy-oriented, and management-oriented strategies. The paper also argues that as important as legal regulation and oversight may be, broader accountability and performance expectations must be addressed at the level of practice, within boards and organizations, and take nonprofit heterogeneity into account.