Procedure for IAS EXAM

The Constituent Assembly of India intended that the bureaucracy should be able to speak out freely, without fear of persecution or financial insecurity as an essential element in unifying the nation. The IAS officers are recruited by the Union government on the recommendation of the Union Public Service Commission (UPSC) and posted under various State governments. While the respective State Governments have control over them they can not censure or take disciplinary action against IAS and other All India Services officers without consulting the Union Government(Central) and the UPSC.
The examination is conducted by the Union Public Service Commission. It has three stages: a preliminary exam, a main exam, and an interview, and is known for being extremely challenging. Recently the preliminary exam pattern has changed. There used to be 23 optional subjects along with a general studies paper. Now there will be no optional subjects in the preliminary examination. Instead there will be a second paper which will be common for all candidates. It covers aptitude, general mathematics, comprehensive English,social studies etc.
Entry into the IAS is considered very difficult. Almost all of the applicants rank IAS as their top choice because of the high prestige and diversity of career it offers. For example, in the 2005 batch, of the 425 selected candidates, 398 indicated IAS as their first preference, 29 chose IRS, and just nine chose IPS. But when it came to second preference, 200 candidates marked IPS as their choice, while only 199 marked IRS as their second choice.
Repeated attempts are allowed up to four times for General Merit candidates, seven times for OBC candidates. There is no bar on the number of attempts for SC/ST candidates. The upper age limit to attempt the examination is 35 for SC/ST and 30 years for the General Merit Candidate. The candidate should not be older than 30 years of age as on 1 August of that year. The minimum age is 21 years.
About 850 candidates are finally selected each year out of the nearly 300,000, but only a rank i.e. top 50 guarantees an IAS selection — an acceptance rate of 0.01 percent, which makes it one of the most competitive selection processes in the world.