Railway ecology is an emerging discipline. In this review, we focus on what is known today regarding the impacts of railways on wildlife, and on the methods to identify, monitor, and mitigate these impacts. Wildlife-train collisions are the most often reported impact, although railway lines can also represent barriers to animal movement, bisecting populations or reducing wildlife access to resources. Little is known on the impact of habitat loss and fragmentation due to railways alone, or on their disturbance effects, including pollution (noise, chemical, light), and on the potential to provide habitat connectivity or surrogate habitats for native species in degraded landscapes. Palabras clave: Ecological infrastructure, Railway