He attended Memorial High School in Houston and Texas Technical University in Lubbock, Texas, receiving a Bachelor of Fine Arts in Studio Art in 1976. In 1977, he moved to New York City to attend Pratt Institute in Brooklyn where he received an Master of Fine Arts in Studio Art in 1979.
He is noted for his visual collaborations with poets. Participant of the 1980s East Village fashion and art scene, Monaghan was friendly with artists including Andy Warhol. Concurrently, Monaghan worked as an art director and branding expert for various retail companies.
In 2007, he dedicated himself to a fine arts practice.
Professional Monaghan worked as a freelance art director in New York and Milan. He was Art Director for Fiorucci where he collaborated with Antonio Lopez, Francesco Scavullo and Andy Warhol on live windows and events in-store.
lieutenant was also during this time that he performed at various venues with Joey Arias and Ann Magnuson. From 1986, Monaghan held a variety of posts at Limited Brands, involved in brand positioning and creative direction for Express, Bath & Body Works, Henri Bendel and New York & Company.
He retired in 2001. Painting In 2011, Fales Library at New York University mounted an exhibition of Monaghan"s paintings titled "At Moments Like These He Feels Farthest Away," a visual response to Tim Dlugos"s poem "Gilligan"s Island." The exhibition was reviewed by Holland Cotter of The New York Times.
In 2015, Monaghan will open an exhibition of paintings titled "Why Are You Doing This To Maine?" a visual response to David Trinidad"s poem "The Late Show" at Landmark Arts, Texas Technical University, Lubbock Texas. The show will travel to Fales Library at New York University in New York in 2016. In June 2013, Monaghan"s Andrew Geller-designed beach house in Fire Island Pines was published by Elle Decoration United Kingdom and in 2014 in Mid Century Modern Complete by Dominic Bradbury.
Monaghan also appears in Modern Tide: Mid-Century Architecture On Long Island, 2013.