Carrageenan seaweed farming based primarily on the cultivation of Kappaphycus and Eucheuma species has grown significantly in the Philippines and Indonesia in the last two decades. Growth has also taken place on a smaller scale in the United Republic of Tanzania and a few other developing countries. Thanks to attributes such as relatively simple farming techniques, low requirements of capital and material inputs, and short production cycles, carrageenan seaweed farming has become a favourable livelihood source for smallholder farmers or fishers and generated substantial socio-economic benefits to marginalized coastal communities in developing countries. However, further development of carrageenan seaweed farming needs to overcome various barriers and constraints such as inclement weather conditions, disease outbreaks, uncertain and fluctuating market conditions, lack of value-added products and value-adding activities in most of seaweed farming countries, low incomes of seaweed farmers in some countries, and occupational health hazards. With six country case studies and one global synthesis, this document attempts to provide a balanced assessment and comparison of the social and economic performance of carrageenan seaweed farming in different countries. Various issues related to seaweed–carrageenan value chains are highlighted. The technical and economic performance of a number of carrageenan seaweed farming cases are systematically evaluated and compared. The positive and negative social impacts of carrageenan seaweed farming are discussed. Issues related to governance and institutions in the sector are reviewed. Challenges and constraints faced by different countries in the future development of their seaweed industries are identified. The document also highlights a series of information and knowledge gaps that need to be filled in order to form a clearer vision of carrageenan seaweed farming development in the future and facilitate evidence-based policy decision-making and sector management.