Intra vires is a Latin legal term meaning 'within the powers' and indicates that a municipality has legal authority to take a particular action. Under Canadian law, municipalities can only do what provincial legislation authorizes them to do. When a municipal decision is challenged in court, judges determine whether the action was intra vires (permitted) or ultra vires (beyond its powers). Modern municipal legislation in most provinces grants broad 'natural person powers,' making intra vires challenges less common than historically. Understanding this concept helps municipal officials ensure their decisions have proper legal foundation.