1. A hybrid probabilistic/deterministic planning system comprising: a computer processor; a hybrid planning engine to run on the computer processor responsive to a null hybrid contingency plan including user defined probabilistic problem including goals, possible effect actions, and the initial state of one or more possible worlds configured to extract a deterministic planning problem therefrom; and a deterministic planning engine responsive to the hybrid planning engine configured to generate one or more deterministic partial plans, wherein said hybrid planning engine converts the one or more deterministic partial plans into one or more hybrid partial plans and splices the one or more hybrid partial plans into selected null hybrid contingency plans to generate one or more hybrid contingency plans for each agent in each of the one or more possible worlds, wherein said hybrid planning engine splices the one or more hybrid partial plans into selected hybrid contingency plans for each agent in each of the one or more possible worlds to generate a plurality of hybrid contingency plans, the selected hybrid contingency plans include at least a hybrid contingency plan for one more uncontrolled agents in the one or more possible worlds and a hybrid contingency plan for one or more controlled agents in the one or more possible worlds, and the hybrid planning engine generates a deterministic planning problem for each of the one or more conflicts.