The compliance of dust-mite (DM) allergic patients receiving immunotherapy (IT) with environmental avoidance measures has not been reported. To investigate patient practices, a questionnaire was distributed to patients receiving IT for indoor allergens. Ninety-three of 200 patients (46%) with indoor allergies completed the questionnaire. Of the 93 patients, 69% were allergic to DMs, 45% were allergic to pets, 17% were allergic to mold, and 3% were allergic to cockroaches. Of 64 patients allergic to DMs, 53% reported use of mattress covers, 61% reported use of pillow covers, 81% reduced moisture in their homes, 83% washed their bed linens in water that was >130 degrees F, 77% vacuumed or dusted weekly, and 21% replaced carpets with polished flooring. Fifty-two percent of patients who did not use covers and 49% who did not replace their carpets cited cost as the most common reason. Education about the use of DM covers was reported by 97% of patients allergic to DMs, predominantly by physicians. In conclusion, many patients on IT for DM allergy do not use avoidance measures for decreasing allergen exposure. Cost appears to influence compliance with several measures including protective mattress and pillow covers. It may be unreasonable to require most patients to use such avoidance measures before being candidates for IT.