Dear Ankita,
For posts in IB, applications are invited by Ministry of Home Affairs for posts of Assistant Central Intelligence in the Intelligence Bureau.
The candidate must have attained the age of 18 years and must not have attained 27 years of age as on the specified date. Upper age limit is relaxable by 5 years for SC/STs; 3 years for OBC; also relaxable for Ex-Servicemen and Central Govt Servants according to Govt orders in force. Minimum Educational Qualification required is degree in Economic or Statistics or Physics and Maths as subjects. Applications in the prescribed format, have to be sent by ordinary post to the Assistant Director, Intelligence Bureau Govt. of India, at one of the addresses specified in the advertisement published in the Newspapers. Advertisement is generally published in 'Rozgar Samachar' or Employment News.