Born in 1939, and a former aeronautical engineer at McDonnell-Douglas, with a PhD in applied mathematics, Glassman first encountered Zen as a student when he was assigned Huston Smith’s The Religions of Man for an English class. He began meditating in the early 1960s and soon afterwards found a teacher in the form of Japanese Zen master Taizan Maezumi (1931–95) in Los Angeles. Glassman went on to become one of the original founding members of the Zen Center of Los Angeles.
In 1980, Glassman moved back to New York City from the West Coast and established the Zen Community of New York. In 1982, he opened Greyston Bakery in Yonkers, New York, to help alleviate homelessness in the area and provide jobs for residents who lacked education and skills. According to the Greyston Bakery: “Since 1982, we have developed and refined Open Hiring, assembling a remarkable team of bakers by hiring without interviews, resumes, background checks, or applications.”
Glassman authored several books, including The Dude and the Zen Master (2013), Infinite Circle: Teachings in Zen (2003), Bearing Witness: A Zen Master's Lessons in Making Peace (1999), and On Zen Practice: Body, Breath, Mind (1999).