論文アブストラクト：Despite the long development of Graphical User Interfaces, working with multiple graphical objects remains a challenge, due to the difficulties of forming complex selections, ambiguities of operations, and tediousness of repetitively unselect-reselect or ungroup-regroup objects. Instead of tackling them as individual problems, we attribute it to the lack of system support to the general selection-action cycles. We propose Collection Objects to not only support a single fast selection-action cycle but also allow multiple cycles to be chained together into a fluid workflow. Collection Objects unifies selection, grouping, and manipulation of aggregate selections into a single object, with which selection can be composed with various techniques, modified for later actions, grouped with objects inside still directly accessible, and quasi-moded for less context switching. We implemented Collection Object in the context of a vector drawing application with simultaneous pen and touch input. Results of an expert evaluation show that Collection Objects holds considerable promises for fluid interaction with multiple objects.