Wiederkehr & Villiger AG is an engineering firm specializing in the planning, design and execution of railway electrification projects. The core activities include: planning and design of railway electrification systems, permitting procedures and construction projects, execution projects and construction management, commissioning of railway electrification systems, and specific services such as return conductor systems, railway earthing, switching systems, overhead line control systems, overhead lines and catenaries, traction power supply and safety-relevant work. The company focuses on the technical planning and implementation of railway electrification projects and does not offer general engineering services.