The marketing system for sea cucumber in South-East Asia is generally inefficient, and marketing channels are multilayered. Information asymmetry encourages proliferation of redundant players in the distribution system, while high transaction costs keep the overall marketing margin high but the price received by collectors low. This paper is limited to establishing the major features of the marketing system for sea cucumber in South-East Asia. The opportunities and challenges associated with this system, especially in relation to expanding production in response to a growing demand, is the primary focus. The potential for aquaculture is also explored. The paper uses secondary data on production and marketing, as well as information/data generated from relevant studies conducted in the Philippines, Vietnam and Hong Kong. The paper also provides a synthesis of results and discussion from available literature on the subject. The first section outlines the marketing system, particularly in terms of features common to countries in South-East Asia. The second section discusses the marketing opportunities and challenges to expanding sea cucumber production in the region. The third section provides a synthesis of common marketing issues, and offers a set of recommendations on how to explore the opportunities, overcome the challenges, and deal with the various issues plaguing the sea cucumber industry in the region.