In order to effectively implement any transport policy, it is essential to study the traffic demand and consequently to have the appropriate movements or trips information, expressed as origin-destination matrices. It is possible to say then, that the generation of origin-destination matrices is crucial for transport planning. Such matrices represent the amount of people travelling or the amount of goods being transported between different zones of an area. There are several ways to obtain origin-destination matrices. Traditional methods like surveys are generally expensive and time-consuming and that is why they are generally implemented only every 5-10 years. As a consequence, decision makers and analysts are often relying on old O/D matrices that need to be updated.