"Stress is a state which is accompanied by physical, psychological or social complaints or dysfunctions and which results from individuals feeling unable to bridge the gap with the requirements or expectations placed on them......stress is not a disease but prolonged exposure to it may reduce effectiveness at work and may cause ill health". This is the stress definition reported by the EU Framework Agreement on Work Related Stress signed 8 October '04 by four workers and employers signatory parties. In order to describe this state of distress, four observation levels can be used, namely data from literature, the subjective symptoms, the related or observed behaviour dysfunctions and the occupational, social performance dysfunctions. Analysis of and interrelations among these four areas can help a better identification of the stress effects and characterize the most frequently observed aspects.