During recent decades, the number of solvent-exposed workers and solvent exposure in many work tasks has diminished. This has led to a decrease in the number of occupational chronic solvent encephalopathy (CSE) atients, but still every year reveals new cases. This book presents the incidence of CSE in Finland during 1995-2007 and the work tasks and solvent exposure related to CSE. It also presents the findings in brain magnetic resonance imaging, electroencephalography, and event-related potentials and discusses their diagnostic value in CSE.