Burnout can be defined as a long-term reaction to occupational stress which involves, particularly, the helping professions. The main aim of this study was the assessment of burnout in a sample of professional and voluntary health care workers and comparison of the two samples on scores from the Maslach Burnout Inventory. Analysis suggests a significant difference in mean scores for Emotional Exhaustion of volunteers vs professional workers. Some evidence has supported the hypothesis of a fourth dimension, called Behavioral Exhaustion, in the burnout syndrome.