In 1920 Lomer was appointed McGill University's Librarian, a position he remained at until his retirement in 1947.
[1][6][5][7] In 1927, he established McGill's Library School as a full graduate course from what had been a summer program.
[9][5] Lomer was consulted on the rejuvenation of Prince Edward Island's library system.
He died January 14, 1970 aged 89 in hospital in Ottawa after being ill for a short while and was buried in Beechwood Cemetery.
[11] Lomer has been described as "undoubtedly the single most important individual in the history of Canadian library education.