Book excerpt: In line with the recommendation of the FAO Sub-Committee on Aquaculture of the Committee on Fisheries (COFI-SCA) made in 2017, as endorsed by the Committee on Fisheries (COFI) in 2018, regarding the preparation of the Guidelines for Sustainable Aquaculture (GSA), the FAO Fisheries and Aquaculture Division organized, virtually, the second Expert Consultation on the development of GSA from 18 to 22 October 2021. Thirteen experts from Africa, Asia, Latin America, the Middle East, and North America attended the consultation. They were supported by seven resource persons and the FAO Secretariat. The objective of the consultation was to discuss and review the drafts of the GSA, the accompanying “Action-Oriented Guidance for Transforming Aquaculture for Greater Contribution to Achieve the SDGs: Key Interconnected Actions to Guide Decision-Makers and Practitioners (AOG)”, and the background document used for the preparation of the GSA and the AOG. The consultation significantly improved these three documents and technically endorsed the drafts of the GSA and the AOG. The experts agreed to the next step of submitting these drafts to the next session of COFI-SCA for further guidance.