He was a leader in building a professional American diplomatic corps, cutting it loose from domestic politics.
He was named one of three Great Civil Servants, along with William Hunter, and Alvey Augustus Adee.
Carr's most prominent success in bringing professionalism to the foreign service was achieving passage of the Lodge Act of April 1906.
It made officers of the Consular Service careerists on regular salaries, rather than amateurs who depended on collecting fees from applications.
He worked with President Theodore Roosevelt on the executive order of June 1906 which ended the patronage system of appointing consuls for reasons of domestic politics, and instead required promotions by merit through competitive examinations.
Wilbur J. Carr died on June 26, 1942, of a heart attack, at Johns Hopkins Hospital.