Stage-I: RMO (Regional Mathematical Olympiad), is the first step in selecting the Indian Team for IMO. 
Eligibility: It is meant primarily for students of Class IX to XII. As special cases, exceptionally talented students from Class VIII may be allowed to appear at the discretion of the Regional Coordinator. 
Day of Examination: Second Sunday of October.
Time duration: 3 hours, containing 6 subjective problems.

Stage-II: INMO (Indian National Mathematical Olympiad)
Eligibility: Only students selected on the basis of RMO(Regional Mathematical Olympiad) from different regions are eligible to appear for INMO (Indian National Mathematical Olympiad) . About 30 students from each region are selected in the order of their merit. Approximately 900 students qualify for INMO.
Day of Examination: Third Sunday of January. It takes place at 28 centres across the country.
Time duration: 4 hours.

Stage-III: IMOTC (International Mathematical Olympiad Training Camp)
Eligibility: The top 35-50 performers in INMO receive a certificate of merit. They are invited to a month long training camp (junior batch) conducted in May-June. They undergo Lectures and Problem Solving sessions. In addition, INMO awardees of the previous year that have satisfactorily gone through postal tuition throughout the year are invited again for a second round of training (senior batch).

Stage-IV: IMO (International Mathematical Olympiad)
Eligibility: The team selected (consisting of 6 students) at the end of the camp, a "leader" and a "deputy leader," represent India at the IMO in a different member country of IMO (International Mathematical Olympiad) each year.
Month of Examination: July.
IMO consists of two written tests held on two days with a gap of at least one day. 
Time duration: Each test is of 4½ hours duration.

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