Epidemiological studies have detected an increased risk of neuropsychiatric diseases among groups occupationally exposed to organic solvents. Psychological studies of solvent exposed workers have investigated both cognitive and sensory and motors functions. Most of these studies have dealt with trichloroethylene, toluene, styrene, and mixtures of organic solvents. Most of these studies have found a decline in the sensory and motor functions. Of the cognitive functions especially short-term memory has proved to be sensitive to solvent exposure. Also some implications of declined visuoconstructive abilities have been found. It has been possible to analyze exposure-response and exposure-effect relationships between exposure and psychological findings only for some single studies, because reliable measures for long-term solvent exposure have usually not been available. The measurement of personality characteristics among solvent exposure workers has been another neglected area.