For over 75 years, ACGIH has been dedicated to the industrial hygiene and occupational and environmental health and safety communities. They have grown and expanded without losing sight of their original goal - to encourage the interchange of experience among industrial hygiene workers and to collect and make accessible such information and data as might be of aid to them in the proper fulfillment of their duties. This original goal is reflected in both their current mission - the advancement of occupational and environmental health - and in their tagline: Defining the Science of Occupational and Environmental Health.