Optimal solutions to some 2500 linear programming formulations were compared to examine the impact of forest regulation constraints. The solutions demonstrate that regulation can be expensive, with no simple rules available to describe how a regulated forest can best be achieved or what rotation age should be used for the regulated forest. The optimal rotation age can be longer or shorter than the Faustmann rotation, but results strongly suggest that the optimal rotation will be close to the Faustmann rotation if long conversion periods are used. The cost of regulation can be sensitive to the length of the conversion period, the initial age distribution of the forest, stability constraints on harvests during the conversion period, and the range of management options and rotation ages possible. Large cost savings are sometimes possible with relatively small increases in the length of the conversion period. The need to hold land idle during the conversion period can substantially increase the cost of regulation. FOR. SCI. 39(2):321-347.