Horst Willhelm Jakob Rittel (14 July 1930 – 9 July 1990) was a design theorist and university professor. He is best known for coining the term wicked problem, but his influence on design theory and practice was much wider.
His field of work is the science of design, or, as it also known, the area of design theories and methods (DTM), with the understanding that activities like planning, engineering, policy making are included as particular forms of design.
In response to the perceived failures of early attempts at systematic design, he introduced the concept of "second generation design methods" and a planning/design method known as issue-based information system (IBIS) for handling wicked problems.
Rittel was born in Berlin. From 1958 to 1963, he was Professor of Design Methodology at the Ulm School of Design in Germany (Hochschule für Gestaltung—HfG Ulm).
- 1963 — 1990 Professor of the Science of Design at the University of California, Berkeley, College of Environmental Design, Department of Architecture and Department of City and Regional Planning
- 1967 Visiting Associate Professor for Architecture and Operations Research at Washington University, St. Louis, Missouri
- 1973 — 1990 Director and Professor at the University of Stuttgart, Faculty for Architecture and Town Planning.
He died in Heidelberg, aged 59.
Rittel coined the term wicked problem in the mid-1960s to describe the ill-defined problems of planning. Rittel and Melvyn Webber published the seminal paper on Wicked Problems in the journal Policy Sciences in 1973. Although the subject of Wicked Problems is sometimes considered to have originated in the Social Sciences, as a professor in a department of architecture Rittel was clear that architectural design problems were also wicked problems.
IBIS (for issue-based information system) is the instrumental version of the understanding of design as argumentation. It is a method to guide the design process and to reinforce deliberation and argumentation. A number of computer-based versions of IBIS have been and are being developed for various computer systems (personal computers and workstations).
The idea of IBIS was conceived in 1968. It has served as a regular teaching tool, in order to demonstrate the typical difficulties of design and the different ways of dealing with them. IBIS was an idea "waiting for an appropriate technology" in order to become more effective and attractive. The various previous applications have been more or less successful, but have suffered from bureaucratic clumsiness. The recent availability of "hypertext" data-structures and user interfaces—even on small microcomputers and moderately priced workstations—has allowed the design of IBISes which are much more "user-friendly" than their predecessors. Today, we have a number of IBIS-programs, developed and implemented on a variety of machines by PhD-students, most recently by Ph.D. candidate Douglas E. Noble. In addition, there is an implementation (gIBIS), developed by MCC, an R&D corporation in Austin, Texas, run by a consortium of 25 leading US-computer companies and dissolved in 2004.
There are considerations to make the concept of IBIS the basis of operating systems for future generations of computers. At present, large scale tests of gIBIS as a tool for supporting hard- and software development are under way in several corporations. The use of IBIS as a management tool and as a means for argumentative treatment of technology assessment is also being considered by several companies in Europe and elsewhere.
Some crucial old weaknesses of IBIS remain the same: the danger of getting lost in the web of cross-references, the lack of a "synoptic" overview of the state of resolution, and the "logic of the next question", i.e. the problem of prestructuring the possibilities for guiding the designers' deliberations into plausible directions.