A native of Dublin, Harman was educated at University College Dublin and Yale University, where he took his BA/MA and PhD, respectively. He has taught German and Irish literature at Dartmouth, Oberlin, Franklin & Marshall, and the University of Pennsylvania. He is editor and co-translator of Robert Walser Rediscovered: Stories, Fairy-Tale Plays, and Critical Responses (1985) and translator of Hermann Hesse, Soul of the Age (1991, edited by Theodore Ziolkowski). He is also a freelance translator for many newspapers and scholarly journals.
Harman gained public recognition for his 1998 translation of Franz Kafka's The Castle, for which he won the Lois Roth Award of the Modern Language Association. As a translator, Harman wrote, "Translation is a complex issue, and retranslation doubly so," referencing the double challenge to confront both the text in the original and in other translations. Harman has characterized the current moment as a "great era for retranslation" to reexamine the versions through which generations of English-speakers have encountered important works from other tongues. A detailed discussion of his work with Kafka's unfinished novel may be found at The Castle, Critical Edition, Harman Translation.
His translation of Kafka's "Amerika: The Missing Person", more widely known as Amerika, was published in November 2008.