His reputation as a printmaker began to take off in the 1950’s and he quickly became internationally known. He showed work in most major print exhibitions throughout the United States, Europe and Japan. His exposure to the Japanese in1956 at the Yoshide Gallery in Tokyo lead to printmaking masters such as Kiyoshi Saito and Jun’ichiro Sekino coming to Seattle to work with Alps firsthand to learn collagraphy. In 1961 Alps was invited to produce a series of lithographs at the Tamarind Institute in Los Angeles, an atelier known for its own important contribution within printmaking, leading to yet another one-man show at the Henry Art Gallery in 1962.
That same year he contributed several prints, sculptures and paintings to the Seattle Worlds Fair Northwest Art Today and Adventures in Art at the Fine Arts Pavilion in Seattle Center.
Out of several book on printmaking which discuss Glen Alps and his contributions the most important is The Art of the Print: Masterpieces History and Techniques by Fritz Eichenberg (Thames and Hundson, London 1976.) The author attested to the importance of his work by including illustrations of Alps work, his working methods and extensive interview in a prominent section of the book. Beside his own career in fine art, Alps was a major influence on several generations of art students and artists during his tenure as professor at the UW School of Art.