The PERQ, also referred to as the Three Rivers PERQ or ICL PERQ, was a pioneering workstation computer produced in the late 1970s through the early 1980s. In June 1979, the company took its very first order from the UK's Rutherford Appleton Laboratory and the computer was officially launched in August 1979 at SIGGRAPH in Chicago. It was the first commercially produced personal workstation with a Graphical User Interface. The design was heavily influenced by the original workstation computer, the Xerox Alto, which was never commercially produced. The origin of the name "PERQ" was chosen both as an acronym of "Pascal Engine that Runs Quicker," and to evoke the word perquisite.
The workstation was conceived by six former Carnegie Mellon University alumni and employees, Brian S. Rosen, James R. Teter, William H. Broadley, J. Stanley Kriz, D. Raj Reddy and Paul G. Newbury, who formed the startup Three Rivers Computer Corporation (3RCC) in 1974. Brian Rosen also worked at Xerox PARC on the Dolphin workstation. As a result of interest from the UK Science Research Council (later, the Science and Engineering Research Council), 3RCC entered into a relationship with the British computer company ICL in 1981 for European distribution, and later co-development and manufacturing. The PERQ was used in a number of academic research projects in the UK during the 1980s. 3RCC was renamed PERQ System Corporation in 1984. It went out of business in 1986, largely due to competition from other workstation manufacturers such as Sun Microsystems, Apollo Computer and Silicon Graphics.