Rai Sahib / Rao Sahib / Roy Sahib abbreviated R.S., was a title of honour issued during the era of British rule in India to individuals who performed great service in visionary leadership to the nation. The title was accompanied by a medal. Translated, sahib means "leader".
The title styled Rai Sahib were awarded to Hindu people of North India, Rao Saheb in Maharashtra and styled Rao Sahib to Hindu people of South India, however, they were both of same category and spelling was altered to meet with regional differences of pronunciation.Whereas, another spelling variation Roy Sahib was awarded to Hindu people of Bengal region of British India.
The Rai Sabib/Rao Sahib/Roy Sahib and other similar titles issued during British Raj were disestablished in 1947 upon independence of India.
Some people awarded the Rai Saheb/ Rao Saheb title
- Rai Saheb Rekhchand Mohota, Bombay - industrialist
- Rao Sahib Polisetty Ranganayakulu Naidu, B.C.E, Indian Civil Engineer, Madras presidency 
- Rao Sahib Ramnath Goenka, Bombay - newspaper editor and businessman
- Rai Saheb Mulji Jagmal Sawaria, Bilaspur, Chhattisgarh - miner.
- Rai Saheb Ruda Ladha Chawra, Hoshangabad - industrialist.
- Rai Saheb Koovarji Karsan Rathor - businessman from Cuttack.
- Rao Sahib P.K.Varughese - Ernakulam - lawyer, founder of St. Mary's Orthodox Cathedral Ernakulam and adviser to the Maharajah of Cochin 
- Rao Saheb Vithalseth Narayanseth Kedari, Excise Contractor, philanthropist, Pune
- C.R. Krishnaswamy Rao Sahib, Padma Vibhushan, Madras - noted Indian administrative officer.
- Rai Sahib H. B. Kanoi of Dibrugarh - tea planter
- RoyalArk Glossary - India
- Hanklyn-janklin By Nigel B. Hankin. 2003. p. 404.
- Image of Rai Sahib Medal
- as rewarded successively with the titles “Rai Sahab”, “Rai Bahadur” and finally, towards the end of the Second World War, “Dewan Bahadur”.
- Introduction to the Constitution of India By Sharma, Sharma B.k.. 2007. p. 83.
- The Rai Saheb Rekhchand Mohota Spinning & Weaving Mills
- St Mary's Orthodox Cathedral, Ernakulam - History
- Ernakulam Bar Association
- Glitz and glamour at the Pune Race course at The Indian Express; published September 14, 2008; retrieved October 17, 2013/
- C.R. Krishnaswamy Rao Sahib passes away
- Assam Tea Planters Association
- All In A Lifetime, Book 1 By Leonard Protheroe. p. 315.