At The University of Melbourne's Conservatorium of Music, McGuire majored in composition, studying with Peter Tahourdin and Barry Conyngham. Hundreds of her commissioned compositions and arrangements are performed around the world. Her works are published with Hal Leonard, Shawnee Press, Yelton Rhodes Music, Coal Creek Publishing and Tresona Music, she is a member of the American Society of Composers, Authors and Publishers (ASCAP) and the Music Arrangers Guild of Australia (MAGA). She was a Semifinalist in the American Prize's Professional Choral Composers division in 2014 and a Finalist in 2015. She received Special Judges Citations on two occasions. Street Requiem - written in collaboration with Jonathon Welch and Andy Payne - received its premiere at the Melbourne International Singers Festival on June 7, 2014, and has since received dozen of performances in multiple countries. Her recent work, No Excuses!, composed with Christina Green, was made possible by grants from Creative Victoria and Brimbank City Council and was performed seven times in its first six months, include on national television. Wirripang, publisher of classical fine music with a focus on music composed by Australian Composers, recently selected Kathleen McGuire through peer review as a new composer in its stable. Her works are also published in the United States by Shawnee Press, Yelton Rhodes and Coal Creek Music.