Just as he created a library journal, so Edmund Lester Pearson created numerous characters for his column “The Librarian.’’ Oscar Gustafsen was among the more endearing and lasting of those characters. This “biography” is largely based on information derived from that column but it has been generously supplemented by information derived from the archives of The Molesworth Institute designed to fill in gaps in Pearson’s data and to more accurately reflect contemporary library concerns and issues. It originally appeared in The Journal of Library History (15:183-7, 1980).