This paper investigates Across-the-Board (ATB) constructions in Japanese, focusing on the differences between vP-coordination and CP-coordination. I argue that ATB vP-coordination, which can target wh-items and requires strict case and polarity matches between the left-edge item and the gap in the second conjunct, is derived through ATB movement. In contrast, ATB CP-coordination, which permits mismatches in case and polarity similar to ellipsis, is explained through pro or ellipsis. Despite criticisms that ATB movement is a construction-specific operation, this paper defends its necessity in Japanese ATB constructions. In addition, this study emphasizes the significance of the conjunct size in determining the structural analysis of ATB constructions.