Abstract: There are needs for pen interaction on a laptop, and the market sees many pen-enabled laptop products. Many of these laptops can be transformed into tablets, when pen interaction is needed. In a real situation, however, a workflow often requires both keyboard and pen interactions, and such a convertible feature may not be effective. In this study, we introduce MirrorPad, a novel interface device contained in a laptop for direct pen interaction. It is both a normal touchpad and a viewport for pen interaction with a mirrored region on the screen. We report findings and decisions obtained from the design iterations that we conducted with users to refine MirrorPad toward the final design. In the user study, MirrorPad showed the same performance as that of the laptop configuration during keyboard interaction and a performance similar to that of the tablet configuration during pen interaction. The user study results confirmed that MirrorPad effectively supports a workflow, which requires interspersed keyboard and pen interactions, thereby achieving its initial goal.