The author supposes that now, in developing a new generation of diesel locomotives it is necessary to place emphasis on interchangeability of units, reliability, diagnostics and automated servicing, ergeconomics and ecology. It is necessary not only to create a new generation of diesel locomotives, but, also, to develop a new system for their servicing and repair. A high medium effective pressure should be achieved in the traction regime to make diesel locomotives highly economical. Several specific examples have been given. The diesel-generator should have a microprocessor system for diagnostics and control. It is underscored that the development of new units should be based on the modification of existing locomotives.