Montgomery was a two-term president of the American Institute of Certified Public Accountants (AICPA).

Two years later the firm opened an office in New York City under Montgomery's management.

In 1905 Montgomery led a reorganization of the American Institute of Certified Public Accountants (AICPA).

[1] Next, Montgomery also got into the field of education by developing a curriculum in accounting for Columbia University.

[4] Montgomery lived in Greenwich, Connecticut, and commuted to work in New York City.

With the help of others he led the effort to establish Fairchild Tropical Garden in 1937, which opened to the public on March 23, 1938.

[7] On 1 July 1998 the worldwide merger of Price Waterhouse and Coopers & Lybrand created the current PricewaterhouseCoopers.

In commemoration of his donation a cultivar of the Colorado spruce was named Picea pungens 'Montgomery' in his honor.

The materials from his collection were featured in a 1987 Rare Book and Manuscript exhibit at Columbia entitled "The Origins of a Great Profession.

Located on 120 acres in Coral Gables, Florida, it includes the largest and finest private collections of palms and cycads in the world.