European freight railway companies face cost pressure and need to increase efficiency in order to keep pace with the competition. A large share of the total costs is due to crews that are required to operate trains. Crew scheduling aims at operating a given train schedule with minimal crew cost. This makes crew scheduling very important, because even small savings in percentages of required crews result in big savings on the bottom line. In this book the author presents foundations of software-based optimization approaches for crew scheduling problems of European freight railways. The focus is put on operations research methods that are used to solve mathematical crew scheduling models. The analysis concentrates on large-scale problem instances of European freight railways, but many of the algorithmic insights hold for other (crew) scheduling contexts as well. While the book is mathematically rigorous, the author presents important managerial insights gained from scenario analyses. Potential readership includes scholars and graduate students who are interested in the fields of crew scheduling and column generation as well as practitioners from transportation companies looking for managerial insights.