In open vehicle routing problems, the vehicles are not required to return to the depot after completing service. In this paper, we present the first exact optimization
algorithm for the open version of the well-known capacitated vehicle routing problem (CVRP). The algorithm is based on branch-and-cut. We show that, even though the
open CVRP initially looks like a minor variation of the standard CVRP, the integer programming formulation and cutting planes need to be modified in subtle ways.
Computational results are given for several standard test instances, which enables us for the first time to assess the quality of existing heuristic methods, and to compare
the relative difficulty of open and closed versions of the same problem.