While PTC may have just recently entered the consciousness of the public at-large, it has been an issue for freight and commuter rail systems since Congress passed the Rail Safety Improvement Act (RSIA) (P.L. 110-432) in 2008 following the collision between a Metrolink commuter train and a Union Pacific freight train in Los Angeles. Since that time, rail organizations have been working toward meeting the federally-mandated PTC implementation deadline of December 31, 2015. With less than six months to go, several commuter rail systems have said that, not only will they not meet the deadline, they will need several more years before having full PTC implementation on their trains.