Abstract: Allergen exposure chambers (AECs) can be used to produce controlled exposure to allergenic and non-allergenic airborne particles but at present cannot be used for double-blind, placebo-controlled, randomized clinical trials currently required by regulatory authorities. Accordingly, inventive naturalistic exposure chambers (NECs) designed to mimic the environment(s) within which a typical user/individual is exposed are outlined. Further, reproducible controlled allergen dispersal is achieved via robotic allergen aerosolization systems (AAS) which provide automated movement of the allergen source within the AEC as well as structure for acquiring and/or aerosolizing—distributing the allergen. Robotic AAS can be used to acquire only, distribute only, or acquire and distribute. Robotic AAS may also provide aerosolization of two or more allergens in defined manner.