On the basis of a critical overview of specialised ergonomics literature and of national and international standards on the subjects, this paper outlines the main ergonomic requirements and characteristics for work chairs. The main ergonomic requirements for work chairs are the following: RESULTS the chair should not be the source or cause of accidents. Adaptability: the chair's dimensions and control features should be such that they meet the anthropometric characteristics of at least 90% of the potential users. Comfort: the chair should be physiologically comfortable for the user. To this end, the following are all important features: seat-plane and backrest contours, backrest height and inclination adjustability, padding and covering materials that allow the body to breath. Practicality: the chair, and in particular the control features, should be practical and easy to control use. Durability: the chair should offer good wear and durability of its components and controls. Suitability for the job: the chair should be appropriately designed for the intended type of job and working environment. For each of these requirements single parameters are considered and for each parameter specific qualitative and/or quantitative data are given in order to class each single item as: "not acceptable", "acceptable" or "good", as regards standards and regulations, anthropometric parameters and intended uses. Criteria are given for a concise assessment of each of the six main requirements and for a comprehensive assessment of the "ergonomic quality" of the work chair.