Thomas "Tom" M. Frost (June 30, 1936[citation needed] – August 24, 2018[1]) was an American rock climber known for big wall climbing first ascents in Yosemite Valley.

In 1960, he made the second ascent of The Nose on El Capitan in Yosemite Valley, a route pioneered by Warren Harding in 1958.

In 1961, Frost and Yvon Chouinard visited the Tetons, and made the first ascent of the northeast face of Disappointment Peak, its difficulty rated IV, 5.9, A3, according to the Yosemite Decimal System (YDS).

[7] In 1963, he visited the Himalaya with Edmund Hillary, making the first ascent of Kangtega, and helping with the construction of a school and a hospital for the Sherpas.

From October 22–31, 1964, with Robbins, Pratt and Chouinard, Frost made the first ascent of the North America Wall on El Capitan, YDS VI, 5.8, A5.

[17] Frost was a longtime advocate of environmental ethics in climbing, using natural protection whenever possible, guided by respect for tradition and a desire to "leave no trace".

He articulated his climbing philosophy in an address to an international congress called "The Future of Mountain Sports", held in Innsbruck, Austria in September, 2002.

He opposed what he believed to be excessive use of bolts by sport climbers, especially the altering of traditional climbing routes previously completed without such aids.

[19] With the support of other activists, Frost initiated a lawsuit against the Park Service, which was joined by the American Alpine Club.

[19] As part of their attempt to stop the construction project, Frost and his attorney Dick Duane also filed an application to have Camp 4 listed on the National Register of Historic Places.

[20][21] In 2002, Royal Robbins offered the following description of Frost: "Tom is the kindest and gentlest and most generous person I have ever met, with never an ill word to say of anyone.

"[22] While working on the first ascent of Kat Pinnacle with Chouinard in 1959, the pair designed and fabricated the Realized Ultimate Reality Piton or RURP, a tiny device that allowed them to finish the most difficult aid climb then completed in North America.