Collaboration: Clamp

Clamp is an all-female Japanese mangaka group that formed in the mid 1980s.

Current actual composition of the team is:
* Ookawa Nanase
* Mokona
* Nekoi Tsubaki
* Igarashi Satsuki

Ookawa Nanase acts as the group's spokeswoman, producer-director, and storyboarder and provides much of the storyline and screenplay for all their works and adaptations of those works respectively. Mokona is the chief character designer, while Igarashi and Nekoi work for the background; however, the three often shuffle their roles. Almost 100 million Clamp tankoubon copies have been sold worldwide as of October 2007.

Clamp originally began in the mid 1980s as an eleven-member doujinshi circle named Clamp Cluster. This included O-Kyon (お·きょん), Nanao Sei (七穂せい), Akiyama Tamayo (秋山 たまよ), Sei Leeza (聖りいざ), Hishika Soushi (日鷺総司), Nakamori Kazue (中森かずえ), and Oumi Shinya (大海神哉). Like many doujinshi groups, Clamp did welcome guests in their team from time to time. For example, Inoue Yuzuru is often listed as the twelfth member of the group but was only a guest. The three artists of Clamp — Mokona, Nekoi Tsubaki, and Igarashi Satsuki — first began drawing manga when they were either in middle or high school, inspired by friends. The three artists were good friends in the same school. They met Ookawa Nanase when one of her friends befriended Mokona after buying a comic that she was selling, and through that connection, the four of them became friends. The original group of eleven members began to meet at every event held in Osaka and Kobe, which usually occurred once a month. Before they began creating original work, the group produced doujinshi of Captain Tsubasa, and yaoi doujinshi of Saint Seiya. However in 1987, the group stopped doujinshi and began creating original work; it was at this time they began working on RG Veda. Their first collaborative work was entitled "CLAMP", which they continued to work on until shortly after their debut.

The group first decided to debut as professional comic writers when they decided to print the manga RG Veda that they had first began working on as a fan comic. After seeing the comic digest of the manga series that Clamp decided to publish, an editor for Shinshokan's Wings manga magazine asked the group to work for them. They submitted an approximately sixty page story as a sample of their talents, however the work was rejected. Ookawa later lauded the draft stating that "everything was bad", attributing the quality to having never before completed a story as a cohesive group and to lack of experience. The group was given another chance at publication should they submit a new story that Shinshokan liked, and they submitted RG Veda.

By the group's professional debut in 1989 with the manga RG Veda, serialised in Shinshokan's Wings magazine, its members had diminished to seven. During the production of RG Veda manga, O-Kyon had left the group, Nanao Sei officially left the group in June 1990 (last mentioned in Shouten 6), and Akiyama Tamayo and Sei Leeza officially left the group in October 1992. Although RG Veda was originally planned to be a single story rather than a series, because of good reader response and higher-than-expected sales for its first volume, Shinshokan permitted the group to create more volumes. After each chapter of RG Veda that the group released, Shinshokan threatened that it would cease serialization should its popularity fall. Hishika Soushi, Nakamori Kazue, and Oumi Shinya officially left in March 1993 (as mentioned in the Shouten 3), leaving the four members who are currently still part of the group.

In 2004, Clamp's 15th anniversary as a mangaka group, the members changed their names from Ookawa Nanase , Apapa Mokona, Nekoi Mick, and Igarashi Satsuki to Ookawa Ageha, Mokona, Nekoi Tsubaki and Igarashi Satsuki (her name is pronounced the same, but written with different characters) respectively. In a later interview with Ookawa, it was revealed that initially Mokona wanted to drop her surname because it sounded too immature for her liking, while Nekoi disliked people commenting that her name was the same as Mick Jagger's. Ookawa and Igarashi, wanting to go with the flow of Nekoi's and Mokona's name changes, changed their names as well. However later Nanase decided to change her name back (from Ookawa Ageha back to her original name Ookawa Nanase).

Mystery has surrounded the members of Clamp as, in order to avoid being harassed by overzealous fans, they avoid making public appearances.

Their work Card Captor Sakura won the Seiun Award for best manga in 2001.