This research estimates the commercial costs and benefits associated with selected aquaculture projects in the Canterbury region. Mussel farming employment will most likely be generated in coastal communities that at present have few employment opportunities. These communities are likely to profit as well from increased infrastructure needs for the marine farming enterprise. Any development in the marine farming industry will take many years to reach full potential. This means that the costs and benefits from increased marine farming activities will be staggered over a number of years. It is acknowledged that the gains might be achieved at different locations than the losses occur. The effects on other stakeholders are often uncertain.