The classical Gordon–Schaefer model presents equilibrium revenue (

) and cost (

, including opportunity costs of labor and capital, in a fishery where the fish population growth follows a logistic function. Unit price of harvest and unit cost of fishing effort are assumed to be constants. In this case, the open access solution without restrictions (

) is found when

and no rent (abnormal profit,

) is obtained. Abnormal profit (here resource rent) is maximized when

(maximum economic yield,

). Discounted future flow of equilibrium rent is maximized when

, where

is the unit rent of harvest and

is the discount rate. This situation is referred to as the optimal solution (

), maximizing the present value of all future resource rent. The open access solution and

equilibriums are found to be special cases of the optimal solution, when

and

, respectively.