SEBI: Securities and Exchange Board of India
Established in 1998
The Preamble of the Securities and Exchange Board of India describes the basic functions of the Securities and Exchange Board of India as “…to protect the interests of investors in securities and to promote the development of, and to regulate the securities market and for matters connected there with or incidental there to”.

SEBI has to be responsive to the needs of three groups, which constitute the market:

issuers of securities
investors
market intermediaries

Headquaters : Mumbai Chairman : Mr. Ajay Tyagi (I’ve met him and shook hands:) )
official site