A stochastic model for stand projection is developed from which difference equations are derived for expectations, variances, and covariances of tree counts. Results are applied to the problems of assessing effects of errors in input and transition parameters on stand projections and of measuring uncertainty in short-term predictions. A worked example illustrates the calculations of expected stand numbers and their variances over a 12-year span and compares them with inventory data. Forest Sci. 19:303-314.