Sustainable use of renewable resources combined with an effort to keep communities sustainable/viable, leads to questions regarding markets, cash and income. All contemporary societies are dependent upon a steady cash flow, and in for example many small communities in Greenland, marine mammal products remain an important source of cash. On the other hand, the pilot whale hunt drives in the Faroe Islands do not generate cash directly, but are an important source of meat for the households. In this sense the monetary replacement value is probably high. The income generated by marine mammal harvesting in Norway is also important to the overall economy of the whaling and sealing communities. Cash income and the nutritional value of marine mammals are likely to be important aspects of Icelandic whaling, if resumed. In all these cases, the social and cultural values of marine mammal hunting and the subsequent consumption and distribution of the foodstuffs must not be overlooked.

One obstacle to the sustainability of marine mammal use in some of the NAMMCO countries is the trade ban on sealskins in Europe (skins from harp and hooded seal-pups only) and the U.S. (all marine mammal products). The sealskin trade ban is not driven by market principles (i.e. international trade issues), and it is no longer motivated by a need to protect endangered species, or by concerns for environmental degradation. It is motivated by animal protectionist arguments stemming from a claim in the 1970s - 1980s, that, in particular, harp and hooded seals were endangered. Later, when it was understood that these species were not endangered, the focus of the anti-sealing controversy shifted to include all seal species. This is because perspectives of humane killing of animals and animal rights motivated the protests against sealing (and whaling). Seals and whales have a unique appeal and the notion that they are killed is disagreeable to many Western people. (This is a large and very interesting topic, but is beyond the scope of this paper.)

What is perhaps unique about NAMMCO is that all signatories have a long history of, and are currently utilizing (or have until recently utilized) marine mammals as a resource. The NAMMCO member countries share a common concern for the various species roaming the North Atlantic Ocean. Marine mammals are important to the economy, for nutrition and to the social organization of many communities in these countries.