For airlines, crew costs make up the second largest expense, behind fuel costs. Because these costs are very high, there is a large potential gain in improving the crew efficiency within the bounds set by the law and collective labor agreements. This thesis investigates the dated crew pairing problem, and how the crew pairing problem can be integrated with aircraft routing and flight retiming in order to achieve more crew-efficient schedules for a low-cost airline operating a point-to-point network. Three different levels of problem integration, non-integrated, aircraft routing integrated, and aircraft routing integrated including retiming, are investigated on real point-to-point airline data, leading to five different models using either a generate-and-test or branch-and-price approach. It is shown that the currently presented models return pairings that reduce the number of duties up to 10% and increase the crew productivity up to 1.5%.