Low-rise RC frames with Infilled walls are widely used in many areas around the world. It is well known that the presence of infill walls can have adverse effects on the seismic response of the frame due to infill-frame interactions. Despite their widespread usage, clear design strategies to prevent undesirable failure modes due to the infill-frame interactions are not normally given in design codes. This paper proposes a practical design method for RC with infilled frames. The method is based on controlling failure mechanism of the frame. The key design assumption was first validated using si Authors: Sutat ,,Leelataviwat;Jarun,,Srechai;Wongsa,,Wararuksajja;Virote,,Boonyapinyo ;Jirawat,,Junruang. Presented at TSER2023.