University of Nebraska system
After teaching at Harvard for several years, Horsbrugh lectured at North Carolina State University as a visiting professor in 1952. During this same year, "High Paddington" was published by Sergei Kadleigh, with Horsbrugh's assistance, describing a vertically built town suitable for eight thousand individuals. After a stint at the University of Illinois at Urbana–Champaign, he spent five years teaching at the University of Nebraska–Lincoln, which was at the time the maximum number of years that a foreigner could be employed with the University of Nebraska system. Although the law was rescinded at the end of his tenure, he had already signed a contract with the University of Texas at Austin, where in 1965 he had planned and hosted a conference on the environmental impact of modern architecture. He spent two and a half more years at the institution prior to arriving at the University of Notre Dame in 1968 to teach environics, a term that he had coined in 1954 to encompass the studies of the interplay between the environment and architecture. During his career he also lectured at the University of California, Berkeley, the University of Florida, the University of Georgia, and Pennsylvania State University.