It is the aim of this article to put questions of maintenance and repair in the history of science and technology under scrutiny, with a special focus on technologies and methods of transportation. The history of transportation is a history of trying to avoid shipwrecks and plane crashes. It is also a history of broken masts, worm-eaten hulls, the flat tires of cars, and endless delays at airports. This introductory article assesses the technological, scientific, and cultural implications of repairing and maintaining transportation networks. We argue that infrastructures for maintenance and repair played just as important a role in the history of transportation as the wharves and factories where ships, cars, trains, and airplanes were originally built. We also suggest that maintenance and repair are important sites of knowledge production, and a historical account of these practices provides a new, decentered narrative for the development of modern science and technology.