Benefit-cost analysis (BCA, also called cost-benefit analysis) is a tool commonly used to estimate the economic consequences of a new project. A development with a ratio greater than 1:1 is said to be economically worthwhile. However, the technique is really valid only for comparing two projects at the one time using an identical method, because estimates by different economists usually adopt different methods or assumptions.
Howard Guille has written an insightful explanation of benefit-cost analysis focused on the Toondah Harbour project, near Cleveland. The article is reproduced with the permission of the author and the Redlands 2030 community website.