The In-Check-Dial (Alliance Tech Medical, Granburg, TX) was used to determine adequacy of inhalation techniques and teaching of two different devices. Retention of adequate techniques, was assessed in 234 moderate to severe asthmatics. Inhalation techniques were assessed at periodic follow-ups divided into less than 1 month return visit, between 1 and 3 months, 3 to less than 6 months, and 6 months to less than 1 year. Proper inhalation techniques worsened at greater than 3 months after the last instruction. The use of the In-Check-Dial is a useful tool in teaching proper technique and monitoring the patient's ability to correctly use inhalation devices.