This paper presents a model and a solving algorithm for integrated planning of rolling-stock and train driver resources in railway transportation (at the national French railway company SNCF). We first propose a mixed integer linear programming model where coupling constraints are introduced to ensure the consistency between the uses of the two resource types. Some numerical experiments obtained with a standard solver are shown and compared with those obtained using a classical sequential approach. Because solving this model for real-life instances with a standard solver is too time-consuming, a Lagrangian relaxation approach is proposed.