Catherine M. Howett, FASLA, (1934–2025) was a landscape architect, historian, and author focused on 19th and 20th-century American architecture, landscape architecture, and public art, with particular interest in environmental art and cultural landscape preservation. Born Catherine Tekakwitha Mahony in New York, New York, to Jeremiah George Mahony (1891-1984) and Julia Nolan Mahony (1895-1985), she attended the Elizabeth Seton School in Yonkers, New York. Howett earned a Bachelor of Arts degree from the College of New Rochelle in New Rochelle, New York, in 1956 and a Master of Arts in English Language and Literature degree at University of Chicago in 1957.

Catherine Mahony married John Spurgeon Howett (1926-2009) in 1957, and they had four daughters, Meghan Howett Magruder, Maeve Howett, Catherine Howett Smith, and Ciannat Howett Marose. The Howett family moved to Atlanta in 1966. Catherine Howett earned a Master of Landscape Architecture degree from the School of Environmental Design (later College of Environment + Design) at University of Georgia in 1976. Howett worked as a recreation planner for the Office of Planning and Research at Georgia Department of Natural Resources from 1976 to 1977, and then as a landscape architect for Ashley Associates in Atlanta from 1977 to 1979. Beginning in 1979 Howett taught at the School of Environmental Design at University of Georgia until her retirement as Professor Emerita in 1999.

Howett curated the exhibition, Land of Our Own: Landscape and Gardening Tradition in Georgia, 1733-1983, at Atlanta Historical Society (later Atlanta History Center) in 1983. Among her many projects was a five-year partnership with sculptor George Trakas (1944- ) at Washington State University. Howett’s academic distinctions and awards include the Bradford Williams Medal of the American Society of Landscape Architects in 1987 and the Outstanding Educator Award from the Council of Educators in Landscape Architecture in 1998. Howett served as visiting professor at the Harvard Graduate School of Design and Senior Fellow of Landscape Studies at Dumbarton Oaks from 1995-2001. In 2004, Howett was elected a Fellow of the American Society of Landscape Architects. She was a board member for the Southern Garden History Society, serving as president and a member of the Publications Committee; and the Alliance for Historic Landscape Preservation, serving on the executive committee. Howett was the author of numerous articles and books, includingThe Gardening Book of James L. Hunter, a Southern Planter, 1996, andA World of Her Own Making: Katharine Smith Reynolds and the Landscape of Reynolda, 2007.