Armstrong first exhibited his work in 1977 and had one-person shows in New York City, Boston, Berlin, Paris, Rome, Zurich, Düsseldorf, Lisbon, Munich, and Amsterdam.
[3] Armstrong entered into the School of the Museum of Fine Arts in Boston as a painting major, but soon switched to photography after studying alongside Goldin, with whom he shared an apartment.
[6] During the late 1970s, Armstrong became associated with the "Boston School" of photography, which included artists such as Nan Goldin, Mark Morrisroe and Jack Pierson.
[4] Armstrong first received critical attention for his intimate black and white portraits of men, lovers and friends, which were shown at PS1's 1981New York/New Wave exhibition, and later published prominently in the monograph "The Silver Cord."
[7] Although he is best known today for his portraits of boys and men, Armstrong's first solo show at Matthew Marks Gallery in 1995 was titled Landscapes.