CEMDA is a legal organization working in defence of the environment and natural resources in Mexico, including the marine regions. Within their broad scope, they include a coasts and seas focus which recently called for the protection of the Veracruz reef. They advocate for the development of national policies regarding coral reefs, such as an Official Mexican Standard on the management and restoration of reef ecosystems. Amongst their many proposals are: an inventory of marine resources, not only those of extractive or commercial importance; a project to establishes the specifications for the preservation, conservation, sustainable use and restoration of coastal wetlands in mangrove areas; geographically defined fishing concessions, under criteria of ecosystem management and social equity; recovery programs for overexploited resources and fisheries management for all species subject to exploitation; create the General Law of Seas and Coasts to change the management of coastal and marine ecosystems; and, finally, prepare the regulations for the General Law on Sustainable Fisheries and Aquaculture.

The principal objective of Centro Ricerca Cetacei is the safeguarding of Mediterranean cetaceans with scientific research projects carried out with strictly non-invasive methods, mainly using eco-compatible sailing boats.

The CSC was established in 1985 as a research group belonging to the Italian Society of Natural Sciences based at the Natural History Museum of Milan. One of the most important aims was to bring together all the Italian researchers and Institutions concerned with cetaceans, encouraging cooperation and studies in this field, and today has a sizable membership. The main project carried out by CSC is a national stranding network that collects data and samples from Cetaceans found stranded or beached along the Italian coasts. Amongst other work, the CSC intervenes in cases where sea turtles and cetaceans become entangled in fishing nets or beach, whether they are alive or dead. The "Luigi Cagnolaro" Recovery and Rehabilitation Center in Pescara is managed by the staff of the CSC and assists all mammals that require assistance and care, before releasing them into the sea, tagged for study

Centro de Conservación Cetacea is a Chilean non-governmental and non-profit organization leader in the conservation of cetaceans and their aquatic ecosystems. Since its creation in 2001 it has achieved great accomplishments in scientific research, educational programs and conservation policies both in the country and in international forums. CCC objectives are:
- To develop non-lethal research programs on cetaceans and their aquatic ecosystems with special emphasis on threatened species. - To integrate the role of cetaceans in the functioning of marine ecosystems in the decision making process of marine conservation policies.
- To design and propose conservation and protection policies for cetaceans and their aquatic environment.
- To identify and evaluate anthropogenic impacts on cetacean populations in order to propose effective mitigation measures.
- To disseminate scientific information to promote active and informed participation of citizens, social organizations and government institutions in cetacean conservation.
- To strengthen cooperation in marine conservation strategies.

The AGHN Marine Conservation Center is a center dedicated to the education, research and conservation of sea turtles and the marine ecosystem that surrounds them.

The Centro de Estudios Marinos (CEM) was established with the aim of developing technical capacities in applied research to support the management of marine biodiversity. Founded in Utila, Islas de la Bahía, as the “Centro de Ecología Marina de Utila”, the Center now works on both the Atlantic and Pacific coasts of Honduras. A significant aspect of their work involves the local fishing community promoting sustainable fishing, marine protected areas, and restoration projects.

CIMAR is a research center attached to the University of Costa Rica, which carries out scientific research to contribute to the knowledge of aquatic environments. Provides public and private institutions repetitive technical services, training and other specialized services.

Based in northeast Scotland, CRRU focuses on the study, conservation and understanding of UK cetaceans (whales, dolphins and porpoises) through scientific research and environmental education. They also provide a 24-hour veterinary rescue service for marine animals in distress. Their outreach programmes include internships, training and a citizen science project for reporting cetacean sightings.

CSI is an all-volunteer, non-profit organization involved in the conservation, education and research of cetaceans (whales, dolphins and porpoises) and their marine environment. Originally the Connecticut Cetacean Society (1974), CCS became Cetacean Society International and is a global leader in cetacean advocacy, with contacts in over 20 countries today. In 2013, CSI became the first US Founding Partner of the World Cetacean Alliance. Their stated purpose includes the following: Oppose rogue whaling and any attempts to overturn the ban on commercial whaling; Promote whale watching as an economic alternative to whaling in developing nations; Represent cetaceans as an NGO at the IWC (International Whaling Commission) and CITES (Convention on International Trade in Endangered Species), and assists regional workshops and meetings, amongst many other initiatives all with the common aim of increasing awareness of the plight of whales, dolphins and porpoises, and to ensure their protection.

Chefs Collaborative Seafood Solutions holds workshops and dining events to help educate and inspire fellow professionals and all eaters about sustainable seafood options

Chelonia specialised in wildlife acoustic monitoring. Since 2006, Chelonia PODs have revolutionised the way cetaceans are studied in the wild. Using fully automated passive acoustic monitoring instruments, it is possible to detect porpoises, dolphins and other toothed whales (except sperm whales) by recognising the trains of echo-location sounds they produce to detect their prey, orientate and interact.

Chesapeake Bay Foundation campaigns for effective, science-based solutions to the pollution degrading the Chesapeake Bay and its rivers and streams