More than half of all computer operators experience eyestrain, headaches, blurred vision and other symptoms directly and indirectly related to increased, sustained nearpoint visual stress. Visual stress also may underlie complaints of general body fatigue, reduced efficiency at work and higher error rates as the day progresses. Optometrists have found that most of these symptoms are alleviated through a combination of correcting workstation conditions, posture, stress-relieving lenses prescribed specifically for computer operation, and in some cases, through improving visual skills with vision therapy.