Commuter Security Group (CSG) is a Swedish security guard company, with its headquarters in Solna. Their main task is to hunt graffiti vandals and prevent vandalism on commuter trains and subway stations. They are also responsible for patrolling and protecting most of the major train depots. In later years they have also expanded to provide security officers who focus on being a visible deterrent in the public transport network.
They were founded in November 2003 under the name CIP Security and have since then expanded rapidly. The company belong to the Keolis conglomerate.