Details about Civil Services examination 

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 subject 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 2011 batch, of the 425 selected candidates, 390 indicated IAS as their first preference, 35 chose IRS, and just 9 chose IPS. But when it came to second preference, 226 candidates marked IRS as their choice, while only 159 marked IPS as their second choice. 

About 850 candidates are finally selected each year out of the nearly 550,000(2010 data) but only a rank in the top 80 guarantees an IAS selection — an acceptance rate of 0.025 percent, which makes it one of the most competitive selection processes in the world.

After being selected for the IAS, candidates are allocated to “cadres.” Most IAS officers start their careers in the state administration at the sub-divisional level as a sub divisional magistrate. They are entrusted with the law and order situation of the city along with general administration and development work of the areas under their charge. The post of District Officer is also known as District Magistrate, District Collector or Deputy Commissioner. Since it is the most identifiable position in the IAS Services , it is also the post which most people identify with IAS. At the top of the hierarchy of IAS officers at the Centre is the Cabinet Secretary followed by Secretary/Additional Secretary, Joint Secretary, Director, Deputy Secretary and Under Secretary. These posts are filled according to seniority.