The recent surge in popularity of ‘accountability’ in public administration and international development seems in part divorced from centuries of conceptual and empirical work done in related disciplines of finance and accounting, and in political science. This article brings together the core meaning of accountability as used in hundreds of previous works, and seeks to bring order to the litany of subtypes in this literature. An organizing scheme with three dimensions (source of control, strength of control, and direction of relationship) captures all the existing varying types of accountability. The resulting typology also clarifies that varying subtypes have not only different actors and characteristics, but also seek to uphold varying values and are facing different challenges. These have important implications both for research and the im-possibility of translating findings from one subtype field to another; as well as practical implications for the policy world. Points for practitioners Accountability has several different forms depending on the actors (e.g. citizens-politicians; politicians-bureaucrats; or judges-citizens). These types of accountability seek to protect different values, and are accompanied by varying challenges. Yet, everything is not accountability: it is but one of many possible ways to constrain the (mis-)use of power. This article clarifies the core idea of accountability. It then depicts the full range of subtypes with their different characteristics and problems. This can function as a guide for policy makers and practitioners when seeking to address weaknesses in accountability of varying actors based on acknowledging their differences.Fundamental to governance is how power and authority are allocated and applied in a variety of public realms: selection of leaders, provision of basic public goods and services (e.g., health, education, transportation and communications infrastructure), maintenance of law and order, revenue generation and allocation, economic and social policy-making, and so on. In all of these realms, public officials, by virtue of the authority accorded the roles and positions they occupy, exercise varying degrees of power as they carry out their functions. What, however, assures that public officials will use their power and authority properly and responsibly? The answer lies with systems, procedures, and mechanisms that impose restraints on power and authority and that create incentives for appropriate behaviors and actions. These all fall within the conceptual and operational boundaries of the term, accountability, which is the topic of this paper. Concerns with limiting power, subjecting authority to a set of rules, and curbing abuses have preoccupied societies for centuries. In today’s world, accountability has taken on a high degree of importance for two main reasons. First, the size and scope of the administrative state in modern economies is large, according governments broad and significant power to intervene in people’s lives. Second, democracy has emerged as the pre-eminent and most aspired-to form of governance system. Thus, the sense that government’s power is dominant, coupled with the desire to see that power exercised according to the will of the citizenry, puts accountability front and center on the stage of current governance issues. In fact, along with transparency and responsiveness, accountability constitutes one of the core components of the definition of democratic governance. Yet despite its centrality to notions of democratic governance and the surface simplicity of the idea of checks and restraints on power, accountability is a “complex and chameleon-like term” (Mulgan, 2000: 555). “Accountability represents an under explored concept whose meaning remains evasive, whose boundaries are fuzzy, and whose internal structure is confusing.” This paper seeks to clarify the meaning of accountability, to elaborate its basic elements, and to offer options for increasing accountability. The focus of the discussion is on countries that are transitioning to, or consolidating, democratic governance systems. The audience consists of democracy/governance officers in the U.S. Agency for International Development (USAID) and in other donor organizations, and host country policy-makers and public managers. Civil society organizations may also find the paper useful. The first section of the paper defines the essential features of accountability and develops a typology. The second section examines accountability in relation to democratic governance, and looks at the different dimensions of accountability, which answers the question, accountable for what? The interconnections among the different dimensions of accountability are discussed. The third section specifies the various categories of actors involved in accountability by asking two questions. Who is accountable? And, accountable to whom? The fourth section discusses issues and options for increasing accountability. It looks at facilitating conditions, and offers targets and strategies for strengthening accountability. The emphasis is on feasibility and fit with politico bureaucratic realities. Throughout the paper, examples are cited.