The use of mild aversives to control self-injurious and stereotypic behaviors of severely emotionally disturbed children is considered. Research is reviewed on the ethics and effectiveness of aversive stimuli. Mild aversives include a form of nonseclusionary timeout known as facial screening, the administration of certain irritating substances such as citric acid and aromatic ammonia, and the use of negative practice. Facial screening (in which the subject's face is covered blocking visual stimuli) studies are cited to show marked reduction of inappropriate behavior. Use of substances (water, lemon juice, and ammonia) is considered, and cautions to their use are listed. Finally, negative practice is characterized as a reduction procedure in which the student is required to engage in exaggerated experience with the inappropriate behavior. The effectiveness of such mild aversives is noted; and advantages of portability, easy administration, ease of training, lack of harm, and lack of expense are cited. (CL)