American-born Canadian urbanologist noted for her clear and original observations on urban life and its problems.

After graduating from high school, Butzner worked at the Scranton Tribune. She moved to New York City in 1934, where she held several different jobs while writing articles for various newspapers and magazines. In 1944 she met and married architect Robert Hyde Jacobs. Already keenly interested in city neighbourhoods and their vitality, both as a writer and—increasingly—as a community activist, she explored urban design and planning at length with her husband. In 1952 she became an associate editor of Architectural Forum, where she worked for a decade.

In 1961 Jacobs published her first full-length book, The Death and Life of Great American Cities, a brash and passionate reinterpretation of the multiple needs of modern urban places. The book, translated into several languages, established her as a force to be reckoned with by planners and economists. The Economy of Cities (1969) discusses the importance of diversity to a city's prosperity, and it, too, challenged much of the conventional wisdom on urban planning. Opposed to the Vietnam War and worried that her sons would be drafted, Jacobs and her family moved to Canada in 1968; she later became a Canadian citizen. Her other works include Cities and the Wealth of Nations (1984) and The Nature of Economies (2000). Dark Age Ahead (2004) centred on the decline of American culture.