The purpose of this article is to present a framework to understand transparency in the third sector and then to explore the main research streams regarding the disclosure of information and accountability by conducting a systematic literature review on the antecedents and dimensions of the transparency of information disclosed by non-profit organizations (NPOs). The essential questions of this work are addressed from an international perspective. In particular, we explore three research questions: (1) why should NPOs disclose transparent information to stakeholders? (2) Why do not all NPOs disclose transparent information? (3) What means do NPOs use to disclose transparent information? Our results highlight the lack of transparency legislation in the third sector, leading NPOs to adopt the voluntary disclosure of information policies to improve the perceived credibility of these entities by their stakeholders. In conclusion, our study highlights the importance of developing a systematic body of knowledge regarding the situation of transparent, voluntary information disclosure in the sector. Moreover, the Sustainable Development Goals promulgated by the United Nations place a high value on transparency for the accountability of institutions. To achieve sustainable development, both peace and the governance of institutions are needed. Reducing corruption and promoting transparency are among the goals which should be reached to achieve social sustainability.

One of the most complex challenges currently faced by non-profit organizations (NPOs) is demonstrating that they manage resources with the highest levels of efficiency and excellence, and do not deviate from the accomplishment of their mission. Transparency and good governance are highly valuable issues for the survival of these organizations. However, empirical studies and models to measure these concepts are scarce and lack consensus. The objective of this article is to develop a uniform procedure for measuring the levels of transparency and good governance in NPOs, validated by experts, that integrates the most important contributions. The main proposals are supported by lists of indicators whose compliance they try to verify. Finally, we considered the experts’ preferences to obtain the indicator weights by means of the Best–Worst Method and Minimum Cost Consensus model. The result of our work is the development of a list of indicators, which integrates the existing battery of Spanish indicators. We contribute, with this work, to improving the credibility of the third sector from the perspective of donors, users, public administrations, and society. This is an essential issue for the survival of these NPOs.

The need of Non-profit Organizations (NPOs) of generating trust and credibility, to their stakeholders by an efficient management of their resources, lead them to openly show that they develop adequate good governance practices. But this is not a simple task and few research has been done on measuring methods of good governance in this field; without achieving an agreement about the best procedure. This paper aims at facilitating the measurement of good governance practices in NPOs by a fuzzy linguistic consensus-based group multi-criteria decision-making (MCGDM) model that will provide agreed and easy-understanding weights for a list of indicators proposed by the stakeholders and entities in such good governance practices. To do that, a linguistic 2-tuple BWM method with a consensus reaching process (CRP) will be developed and then applied to a real-world case in Spain, in which a group of experts from significant Spanish NPOs will assess the list of indicators proposed by the most representative entities (the alliance between the non-governmental organizations (NGO) Platform for Social Action, and the NGO Coordinator for Development (CONGDE) to obtain a prioritization of such indicators for measuring the good governance practices in Spanish NPOs.