The guideway is the most expensive item in a PRT system. Yet in all but a few cases the design of the guideway was more or less an afterthoughtsomething that did not require a great deal of attention. This is a major reason many PRT systems have not survived. Primary attention had to be placed on the development and design of the control system because it was the single technological advance that made consideration of PRT possible. With limited resources, control downgraded the importance of everything else about a PRT system. During the long history of PRT development and design, guideways have been designed for Veyar, Monocab, TTI, StaRRcar, Uniflo, Dashaveyor, Morgantown, The Aerospace Corporation PRT System, Cabintaxi, CVS, Aramis, ELAN-SIG, VEC, Swede Track, Mitchell, SkyCab, Taxi 2000, PRT 2000, Microrail, Skytran, MonicPRT, ULTra, Vectus, and others. This plethora of designs likely has had much to do with the reluctance of city planners to recommend PRT. No two of these guideway designs are very close to each other. Now that the control problem is well understood, it is time to turn more attention to the guideway. The purpose of this paper is to stress the importance of adequate consideration of guideway design requirements and criteria as the basis for the design of guideways that have the potential of becoming standardized and widely deployed.At the University of Minnesota early in my work on PRT I coordinated a Task Force on New Concepts in Urban Transportation. We conducted planning studies of PRT for Minneapolis, St. Paul, and Duluth and soon saw that such studies were mandatory to real understanding of the problems of designing and installing a PRT system, including its guideway. We discussed our work with many public officials, planners, and interested citizens not only in Minnesota, but in many locations around the United States, Canada, Europe, and Asia. We reviewed the work of the many government-funded studies related to AGT design. The most helpful for guideway de-