Collation/Collating is the organizing and assembling of trading cards into complete sets or subsets. Typically done by collectors or dealers, this process involves gathering individual cards and arranging them according to specific criteria, most often using checklists. Collating can be challenging and time-consuming, particularly for larger sets containing many parallels. Collation/Collating is a critical aspect of the Hobby because it allows collectors to complete sets and increase their overall value. Since the introduction of the checklist in the late 19th century, collation/collating remains an essential part of the Hobby requiring patience, attention to detail, and deep knowledge of the cards and sets collected.