George Dantzig in the context of "Mathematical statistics"

The vehicle routing problem (VRP) is a combinatorial optimization and integer programming problem which asks "What is the optimal set of routes for a fleet of vehicles to traverse in order to deliver to a given set of customers?" The problem first appeared, as the truck dispatching problem, in a paper by George Dantzig and John Ramser in 1959, in which it was applied to petrol deliveries. Often, the context is that of delivering goods located at a central depot to customers who have placed orders for such goods. However, variants of the problem consider, e.g, collection of solid waste and the transport of the elderly and the sick to and from health-care facilities. The standard objective of the VRP is to minimise the total route cost. Other objectives, such as minimising the number of vehicles used or travelled distance are also considered.

The VRP generalises the travelling salesman problem (TSP), which is equivalent to requiring a single route to visit all locations. As the TSP is NP-hard, the VRP is also NP-hard.