A least squares estimator for utilizing forthcoming information to update or revise estimates of the parameters of an econometric model is derived, some properties of the updated estimates are discussed, and an illustrative application is provided. The forthcoming information includes new sample observations and a priori probabilistic information about changes, if any, occurring in the parameters of the estimated model over time. Recursive formulae for sequential updating of the parameter estimates are derived. The procedure is used to update estimates of the parameters of an equation describing annual net changes in the inventory of Australian beef cows.