This paper describes a simple technique to improve the process latitude for contact and via printing. The technique applies a selective upsizing algorithm to the mask data during the mask preparation step. For each contact or via, the algorithm looks for available spaces by checking relevant layers near it. When spaces are available, selective edges of a contact or via will be sized to improve the process latitude. This paper describes algorithms used to implement this technique. Multiple designs of various design styles are used to demonstrate the effectiveness of the algorithms. The implications on mask preparation, mask making and wafer processing are also discussed.