Tourism is important to the economy of coastal towns in Namibia, but lack of regulation in the marine tourism sector has the potential to have negative long-term impacts. For the first time, the extent and activities of marine wildlife-watching tourism (MWWT) throughout Namibia are documented. Data on MWWT in Walvis Bay, where the industry is most developed, were collected via interviews. 11 companies offered tours in 2010, providing the equivalent of at least 80 full-time, year-round jobs and direct revenue of over N$ 30 million. A voluntary Code of Conduct has been in place for several years but is not adhered to and cetaceans are frequently exposed to close approaches by vessels, raising concerns for the sustainability of the industry.  Keywords: Sustainable tourism, Code of Conduct;, whale, dolphin, Cape fur seal, Walvis Bay, Cape Cross.