In this paper we investigate the class of control strategies that are optimal for estimation in the context of various multiple regression models whose error terms are not only contemporaneously correlated across equations, but also autocorrelated over time. Specifically, the design optimization problem in the context of the traditional multi-variate regression (reduced form) model, the generalized multivariate regression (Zellner's 'seemingly unrelated regression equation') model, the multivariate regression model with common parameters (cross-section and timeseries) model, and the dynamic multiple-equation regression (varying parameterKalman) model is considered. Since restrictions of coefficients implied by the model structure cause the design criteria to depend on the unknown parameters, the estimation control problem is formulated in a sequential framework and this approach, which is computationally efficient, is shown to resolve the conceptual difficulties inherent in alternative formulations. The maximum accuracy problem considered in this paper can also be treated as an initial phase of a stochastic control problem. This will avoid solution to a difficult dual-control problem.