At KPCO, postcards are typically sent to members each fall, to remind members to receive their annual influenza vaccine. At KPCO, interactive voice response (IVR) systems have been utilized for a number of prevention reminders, but have not in the past been used for influenza vaccination reminders. For the 2012-2013 influenza season, the PPS department is going to send three different types of reminders to their adult patients with certain chronic lung diseases (specifically, adults with asthma and COPD): postcards only; IVR reminders only; postcards plus IVR reminders. This study seeks to evaluate the effectiveness, and cost-effectiveness, of an already-finalized operational plan for influenza reminders.