A primary symptom of Parkinson's Disease, akinesia, progressively restricts the ability to walk. Paradoxically, Parkinson's patients have little difficulty stepping over objects in their path, even when they are totally unable to initiate a step on open ground. Virtual reality technology provides a way to take advantage of this phenomenon to enable walking, by presenting virtual objects overlaid on the natural world. Normal stride length, and even running, can be enabled, provided the virtual cues are spaced properly and simulate the appearance of staying stable on the ground as the person moves. Other movement symptoms of Parkinson's and side effects of its pharmacological treatment have also been shown to be influenced by visual cues.