He graduated in 1947, but stayed on at Berkeley to study for a master's degree in linguistics under Chao Yuen Ren, which he completed in 1949.

He completed his dissertation on Japanese morphophonemics in 1950 (published as a monograph by the Linguistic Society of America the following year), and was immediately offered a position at Yale University, where he remained until his retirement in 1994.

During the 1960s Martin extended his linguistic talents to studies of the Dagur language (1961), and the Shodon dialect of Ryukyuan (1970).

He also published articles on subjects that had been very little studied until that time, such as sound symbolism in Korean (1962) and speech styles in Japan and Korea (1964).

In addition to his scholarly linguistic works, Martin was interested in the teaching of East Asian languages, and he wrote a number of elementary texts and dictionaries for beginners.