Born in Belarus as Shmaryahu Lubetzky, he worked for years at the Library of Congress. He worked as a teacher before he immigrated to the United States in 1927. He earned his BA from UCLA in 1931, and his MA from UC Berkeley in 1932. Lubetzky also taught at the UCLA Graduate School of Education and Information Studies, then the School of Library Service.
Fluent in six languages, Lubetzky published three groundbreaking books that greatly advanced the discipline of cataloging, the organization of knowledge, and modern research methods, still influential in areas of information technology. Librarianship in particular and information science in general had not been revolutionized as much since the likes of Antonio Panizzi, Charles Ammi Cutter or Paul Otlet. Cataloging Rules and Principles and Principles of Cataloging, as well as several periodical articles, solidified Lubetzky as one of the most significant influences in his field. Lubetzky's theory of cataloging went far beyond the Dewey Decimal System. He developed a rationalized approach to catalog code design, one that is even more relevant today as current cataloging principles are revisited and revised for a digital environment.