United States of America Mathematical Olympiad

The United States of America Mathematical Olympiad (USAMO) is a highly selective high school mathematics competition held annually in the United States. Since its debut in 1972, it has served as the final round of the AMC series of contests. The United States of America Junior Mathematical Olympiad (USAJMO) was introduced in 2010 to recognize top scorers based on their AMC10-based index. Qualifying for the USAMO is considered one of the most prestigious awards for high school students in the United States, with only 264 students qualifying in 2013 out of over 350,000 students competing. Top scorers on the USAMO are invited to the Mathematical Olympiad Summer Program to represent the United States at the International Mathematical Olympiad.

In order to be eligible to take the USAMO, a participant must be either a U.S. citizen or a legal resident of the United States or Canada. Only U.S. residents and citizens may join the American IMO team. In addition, all participants, regardless of geographic location, must meet qualification indices determined by previous rounds of the AMC contests. Entry to the USAMO is by invitation only.

The USAMO was created in 1972 at the initiative of Nura D. Turner and Samuel L. Greitzer, and served as the next round to the AHSME until 1982. In 1983, the American Invitational Mathematics Examination was introduced as a bridge between the AHSME and USAMO. In 2010, the USAMO split into the USAMO and USAJMO.

The USAMO (and the USAJMO since 2010) is restricted to approximately 500 (250 prior to 2006) participants combined each year. To keep this quota constant, the AMC Committee uses a selection process, which has seen a number of revisions in the exam's history.

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