"The Working Group on CSO Development Effectiveness (WG on CSO DE) of the CSO Partnership for Development Effectiveness (CPDE) in collaboration with Voluntary Action Network India (VANI) launched the CSO Accountability Documentation Project as part of its mandate of spearheading the promotion and implementation of the Istanbul Principles, and the International Framework on CSO Development Effectiveness, among CSOs from different geographic and sectoral backgrounds. The CSO Accountability Documentation Project was launched to highlight the importance of CSO accountability in advancing discussions on CSO DE, and how this agenda can be used by CSOs to concretely demonstrate their legitimacy, transparency and organizational effectiveness. This document is divided into two broad sections. The first part of the document aims to bring CSOs into a common understanding of CSO legitimacy, transparency and accountability, as this relates to the development effectiveness agenda. The second part of the document deals with the current state of CSO Accountability globally by providing evidences on mechanism and initiatives implemented and subscribed by a number of CSOs. The paper also includes a training guide on CSO Accountability. "