Special Ability Institute (特力研 Toku Ryoku Ken?, lit. "Special Power Laboratory") or Special Esper Institute, formally named as Special Esper Dual Modification Technology Research Institute (特例能力者多重調整技術研究所 Tokurei Nōryokusha Tajū Chōsei Gijutsu Kenkyūjo?) is a now-defunct research facility located in the 10th School District[1], specializing in the research of Dual Skill.[2]


The institute's main function was for the research and experiment on Dual Skill, a theoretical phenomenon where an esper simultaneously manifests two abilities. The institute was said to perform inhuman experiments on people, and used Child Errors as human guinea pigs for their experiments.

Accelerator was kept in the facility until the age of nine due to his unique powers before being moved into another facility, here, he confirms that Child Errors are indeed used in experiments. Yomikawa Aiho's unit of Anti-Skill later dismantles the facility.[2]


  1. Encylopedia of Index-Librorum-Prohibitorum page 72
  2. 2.0 2.1 Toaru Majutsu no Index Light Novel Volume 12