Abstract
Solving the Vehicle Routing Problem (VRP) and its related variants is at the heart of scientific research for optimizing logistic planning. One important variant of the VRP is the Vehicle Routing Problem with Time Windows (VRPTW), where it is assumed that a number of clients must be served by a fleet of vehicles operating from a central depot. Solving this problem requires finding a set of minimum cost routes for the vehicles, while observing a number of pre-defined problem constraints. Since the VRPTW is NP-hard, solving it using exact methods is very time consuming. Heuristic and meta-heuristic approaches are usually the preferred option for solving practical size problems. In this paper, we describe the problem and explain some of the most popular heuristic techniques that have been applied for the solution construction and the solution improvement phases of the problem.