The process capability indices have been widely used in manufacturing industries to provide numerical measures of process potential and performance. This study is concerned with process controls and adjustments by incapability index Cpp and its sub-indices. A monitoring for C^pp would provide a convenient way to monitor changes on process capability after statistical control is established, since Cpp simultaneously measures process variability and centering. Further, we can separate charting of process location and variability by sub-indices of Cpp , (Cia, Cip ), without returning to x -R chart, even though an out-of-control signals on C^pp control chart is found.