Gallagher received a BFA in Painting from the Rhode Island School of Design where he also studied Architecture. He is a recipient of resident fellowships from the MacDowell Colony and the Virginia Center for the Creative Arts. Since coming to Maine in 1975 he has taught as visiting faculty at the College of the Atlantic in Bar Harbor and exhibited in Mane Painting Biennials at Bowdoin College, the Portland Museum of Art and the Maine Drawing Biennial Invitational at the Portland Museum of Art. He received a Maine Arts Commission Individual Artist Fellowship in 1990 and exhibited recent work in a solo show at the University of Maine Museum of Art in the Fall of 2014.
He has had a long career as a patent and technical illustrator, was employed as a project architect at Elliott Elliott Norelius Architecture in Blue Hill and continues a residential design practice.
"The images in my work have evolved and become more defined over the years since I came to live in a small coastal town in Maine in 1975. There is something here in the constant, unrelenting surround of woods and ocean, of rocks and fields, that suggests a continuum, a pulse that runs through everything and seems to imbue objects and forms, a particular rock or tree or rusted scrap of metal in the middle of nowhere, with a sense of mystery and meaning.
"I use these observations as a basis for inventing and improvising forms and images which reflect this mystery and scheme of things."