Environmental economic Note on Identifying Costs and Benefits Cost-benefit analyses is a way of answering the question, “Is this worth doing?” and “How will we know whether it was worth it when we’re done?” It assesses the value of a project by comparing its costs to measures of its performance, or more generally to the value of benefits it produces. The analysis requires accurate cost data (or at least reasonable and defensible estimates), as well as measures of benefits in comparable units of measurement (i.e. money, preferably but not necessarily only money).