In the early 1960s, President Quigg Newton, campus administration, and the Colorado architectural community acted to change the way campus building design occurs. A new campus development plan was created by Sasaki, Walker and Associates, headed by Hideo Sasaki, chair of the Department of Landscape Architecture in the Harvard Graduate School of Design, and consulting architect Pietro Belluschi, dean of the School of Architecture and Planning at the Massachusetts Institute of Technology (MIT). Their plan sustained Klauder's design principles, materials, and humanistic spirit but allowed flexibility to incorporate new concepts and forms. For example, concrete became used for exterior walls, and often replaced the use of limestone for trim. Indigenous sandstone walls and clay barrel tile roofs still predominated, but in more flexible ways, continuing to visually link Klauder and post-Klauder building. The institution also severed the tie to a single architectural firm. Instead, depending on who is best suited to the task at hand, a variety of architects are commissioned to design campus facilities, with continuity ensured by campus staff and the university Design Review Board.
CU grew rapidly during the 1960s, campus building space doubled from the early 1960s to the mid-1970s. New academic and administrative buildings soon surrounded the main student residential area, which had been on the eastern periphery of campus. New student housing, the Kittredge Complex, was built on the southeastern edge of Main Campus in 1963 and 1964. The first major academic building to not slavishly follow the Klauder style, yet inspired by that style, was the Engineering Center in 1965, which, with its extensive use of concrete and introduction of shed roof forms, remains controversial. Stearns and Darley towers, a brick high-rise residence hall complex, were built in 1966 and 1969 on the newly acquired Williams Village.
The Soviet Union's launch of the Sputnik satellite in the late 1950s presaged a new era of campus construction in the late 1960s and 1970s, with the federal government funding science buildings in a race to catch up. The Duane Physical Laboratories complex and the Life Sciences Laboratories complex (Muenzinger Psychology and Porter Biosciences) were among buildings of this period. Scientific research at CU accelerated. Adherence to Klauder's architectural style during this era meant that CU-Boulder avoided the "modernist" style, often poorly interpreted on college campuses.
In 1971 the State Legislature established an enrollment limit of 20,000 FTE (full-time equivalent) students for the Boulder campus. The capping of enrollment signaled the transition of the campus from rapid growth to maturity, although the enrollment limit was later removed. Campus maturation meant an emphasis on renovating existing facilities where possible and developing new space to support CU's growing role as a major research institution. The "postmodernist" era, which began in the 1970s, has revalidated creative use of historical styles, with their richness of material and form, and fit neatly with Boulder's already well-established Tuscan vernacular style.
In the 1980s and 1990s, attention turned to older buildings needing rehabilitation, such as Old Main, Macky, Hale, the Power House, and the Women's Cottage, all of which have benefited from appropriate renovations, giving the oldest buildings new life while preserving their heritage.
Most recently, the challenge again is to accommodate an increase in enrollment, this time for the children of the postwar "baby boomers." At the same time, CU-Boulder remains committed to preserving its reputation as one of the most beautiful higher education campuses in the nation. In order to maintain a fine campus while accommodating dynamic programs and projected enrollment growth, development will increasingly occur on East Campus and Williams Village sites, and at CU-Boulder South. The CU living and learning environment is sustained by a campus that speaks, through its architecture and campus planning, about its history and concern for quality.