In this paper a reactive scheduling technique for multipurpose plants is presented. A Mixed Integer Linear Problem (MILP) formulation is used based on the State Task Network (STN) representation of Kondili et.al. (1993). In order to obtain short response times a rolling horizon is utilized, which is reasonable as far as it is considered a reactive context where perturbations in the future are expected. To bring into consideration time constraints outside the rolling horizon a lookahead characteristic is introduced.