The Clinical Corner article, Manual Mobility: The Basics, describes the different categories of manual wheelchairs, known generically as transport, standard, custom folding, custom rigid and tilt-in-space. It was noted that the more rigid the wheelchair, the easier it is to propel the chair as rigidity decreases flex in the frame of the chair. The ideal is that all of the energy of propulsion is translated into movement as any frame flex is lost movement. The more rigid the wheelchair, the more efficient the propulsion can be. This is one of the reasons that custom rigid wheelchairs are selected for individuals. Sometimes, however, an individual requires a custom folding wheelchair to suit their needs. In this case, it is important to understand how rigidity can be enhanced in a folding frame wheelchair in order to optimize efficient propulsion. (Recall that rolling resistance also effects efficiency of propulsion. See the Clinical Corner article, Rolling Resistance in Manual Wheelchairs, for more on rolling resistance.) This month’s Clinical Corner article will look at some of the ways in which rigidity can be enhanced in a custom folding wheelchair.