Among the nation's oldest athletic clubs, the Boston Athletic Association was established on March 15, 1887 under its first president, Robert F. Clark, and with the support of leading sports enthusiasts, entrepreneurs and politicians of the day. According to Article II of its 1890 Yearbook Constitution, their objective was to "encourage all manly sports and promote physical culture."

The magnificent B.A.A. clubhouse on the corner of Exeter and Boylston Streets in Boston's Back Bay was completed in 1888, on the present-day site of the new Boston Public Library. In addition to such facilities as a gymnasium, bowling alley, billiard hall, Turkish baths and tennis courts, the Association also owned a shooting range and a country club. Among the active sports of the day were boxing, fencing, water polo and athletics.

The club held its first organized track and field competition in 1890 and in 1897 the first famed Boston Marathon took place. A mythical unicorn was chosen as the Association's symbol, and remains on the Boston Marathon medals to this day.

In 1936, the Clubhouse was closed due to financial hardship and the Boston Athletic Association is now headquartered at 40 Trinity Place. In 1986, John Hancock Financial Services Inc. assumed the sponsorship of the Boston Marathon and saw the race into the next millennium.

The B.A.A continues to rely on the generous support of John Hancock and other sponsors and contributors not only with its signature event, the Boston Marathon, but also in its year-round community programming.