Planning for and anticipating the unknown, or the possibility that things probably won’t go as expected, is called “contingency planning”. Contingency planning is vital in any project task when results and outcomes cannot be absolutely guaranteed. Often a contingency plan needs a budget as there are usually costs associated with the possible project unknowns. Contingency planning is about preparing alternate actions, and making sure that extra time, for activity and replacement resources exists to address plan changes. It may be difficult to anticipate precisely what contingency to plan for in complex long-term projects, in which case simply a contingency budget is provided, to be allocated later when or if it is required.