From Wikipedia:
History of Introduction of LHB Coaches in Indian Railways
During 1993-94, Indian Railways decided to look for a new passenger coach design which would be lighter and are capable for higher speeds compared to the existing rakes. Main features of the Railways specification was India's need for high speed light weight coaches to run in Indian Railways within the present infrastructure i.e. specific railway and track conditions along with the specific environmental conditions in India and the operating speed of 160 km/h.[12][4] It was decided by the Railways that the design...
more... would first be tried in the Rail Coach Factory in Kapurthala (RCF), and upon successful completion of this trial, it would be tried in the Integral Coach Factory in Perambur.[5]
In 1995, after a global selection process, Alstom-LHB received the order from Indian Railways to design and develop a new passenger coach under a transfer of technology agreement.[12] As part of the order, Alstom-LHB had to execute two contracts, one for the supply of "Light Weight High Speed Coaches for Broad Gauge"[4] which includes the development, design and manufacture of 19 AC 2nd Class Chair Cars, 2 AC Executive Class Chair Cars and 3 Generator-cum-Brake vans[11] and the other contract for the "Transfer of Technology" which includes the transfer of technology for design and manufacturing, the training of Indian Railways personnel in the premises of the manufacturer and the technical assistance at RCF during the start of production.[5] Out of the 24 coaches imported from Germany, all of them mostly being Air Conditioned chair cars[13], the first lot were used for New Delhi-Lucknow Shatabdi Express on a trial basis. It didn't turn out be successful as the coaches' wide windows were targets of mischief and stone-pelting. Railways had to use sealing tapes to tape up the bruised windows.[12] When these rakes were brought into service, couplers came unstuck and the data collected from the passenger feedback showed that the air conditioning was not "very effective". They were withdrawn from service and after attending to the problems, Railways reintroduced them on the New Delhi-Lucknow Shatabdi Express and proved successful.[12][14]
The RCF began to manufacture other variants of LHB design like the air conditioned first class, AC 2 tier sleeper, AC 3 tier sleeper, hot buffet (pantry) car etc., from 2001-02 and rolled out its first rake in December 2002. The first such rake was introduced for Mumbai-New Delhi Rajdhani Express in December, 2003.[13] The Up to March 2011, 997 LHB coaches were produced by the RCF.[15][16] All of these coaches are being used in premier super fast express trains like Rajdhani, Shatabdi and Duronto Express and have been offering better passenger comfort.[17]