Abstract: Sustained timber yield and the Normal Forest Model represent traditional forest management,which takes sustained timber production as major objective.However, these goals have essentially changed from sustained timber production to sustainable forest management.The objective of forest management is changing from the provision of an optimal mixture of forest commodities to the maintenance of ecological integrity,which depends largely on biodiversity of the forest ecosystem.Given this profound change of objective,a Natural Disturbance Model and forest management sustainability,suitable for maintenance of biodiversity and in compliance with the objective,are developed.Sustained timber production and the Normal Forest Model remain appropriate for commercial forest management,especially for intensive commercial plantations.