Centralised Accident and Trauma Services 
Centralised Accident and Trauma Services (CATS) was visualized as a planned scheme under 6th five year plan in 1984. The scheme was contemplated to be implemented by the Central Govt. under the aegis of AIIMS. Since the service required multi-sector co-ordination of agencies viz,: DFS, Hospitals, Police and other CIVIC BODIES, it was decided that the entire scheme be transferred and implemented by Govt. of Delhi. In June 1989, CATS society was consequently formed and registered under Society registration act 1860.
CATS launched an Ambulance Service on pilot basis in west Delhi on March 15, 1991 with fourteen ambulances at three Ambulance Stations in (a) Deen Dayal Upadhyay Hospital,Hari Nager (b) Sanjay Gandhi Memorial Hospital ,Mangol puri (c) MCD Hospital Moti Nagar.Later on three more stations were opened at Sarai kale khan,Rohini and Shahdara.
In 1997 , the ambulances were stationed on 25 accident prone sites called location points for round the clock operation. In 2001, 30 Nissan Ambulance were procured by Govt. of Delhi on Japanese grant and were handed over to CATS for operation. In 2010, 21 ALS and 10BLS ambulances were received from Department of Health and Family Welfare, GNCTD during common wealth games . These were Advance Life Support and Basic life support ambulances. In the years 2012 & 2013 , 120 Patient Transport Ambulances were added to the existing fleet under NRHM scheme of Govt. of India . In the year 2016 , CATS outsourced the operation and maintenance of CATS ambulances. Presently, M/s GVK EMRI is the outsourced agency which started operation w.e.f 01.07.19. Now CATS has a fleet of 240 Ambulances.
CATS started operation of 16 First Responder Vehicles ( FRVs) in February 2019 for congested areas of East Delhi which are helpful in decreasing the response time by reaching the patient and stabilizing the condition before arrival of the ambulance.