There is increasing competition for the use of the coastal zone as economic development proceeds. This has resulted in the recent release of a Green Paper by the Queensland Premier's Department on coastal zone management. Economic development and conservation appear rarely, if ever, to be completely compatible, and the use of the coastal area for the development of aquaculture can have some adverse environmental effects. In Australia, aquaculture is relatively underdeveloped and the McKinnon Report sees scope for its expansion. A recent report prepared for the United Nations is also optimistic about the prospects of expanding supplies of fishery products by means of aquaculture. But environmental constraints on and production sustainability problems for mariculture are largely ignored in such reports. Giant Clam farming is a new mariculture possibility and has been developed as a response to dwindling wild stocks of giant clams. Most species of giant clams are now listed in the Convention on International Trade in Endangered Species (CITES). While giant clam farming has a number of desirable environmental features and self-sustaining properties compared to other forms of mariculture, it is not without some adverse environmental consequences. But in certain situations the economic benefit from farming giant clams can be expected to outweigh adverse environmental consequences. It pointed out that the environmental impact of mariculture of giant clams varies with the techniques adopted for their cultivation.