The authors report on measures of distress in 26 subjects who had been diagnosed with environmental illness (EI) by a “clinical ecologist.” EI subjects were more likely than control subjects to meet criteria for one or more personality disorder diagnoses assessed with the Structured Interview for DSM-III Personality Disorders and exhibited more somatic, mood, and anxiety symptoms assessed with the Symptom Checklist-90-R and the Illness Behavior Questionnaire. The authors conclude that subjects receiving this diagnosis may suffer from unrecognized psychological distress, which may account for some or all of the symptoms that had resulted in a diagnosis of EI.