The Indian Revenue Service (IRS) is the largest Group A Central Service. It is one of the most important services since it is concerned with the collection of revenue in India. It functions under the Department of Revenue of the Ministry of Finance and is under the administrative direction of the Revenue Secretary and the ministerial command of the Minister of Finance. The IRS plays a crucial role mainly in the implementation of the direct taxes laws through the Income Tax Department. The Income Tax Department is one of the largest Government departments in India with about 75,000 employees spread across 550 locations. Almost every district of the country has an Income Tax office.
The IRS comprises two branches, Indian Revenue Service (Income Tax) and Indian Revenue Service (Custom & Indirect Taxes), controlled by two separate statutory bodies, the Central Board of Direct Taxes (CBDT) and the Central Board of Indirect Taxes and Customs (CBIC).