Open Door, Inc. engages in the management and operation of the travel comparison sites. It operates through the following business divisions: Travel Content and Other Content. The Travel Content business division manages a travel comparison site called 'Travelko', which allows customers to search travel products in either Japanese or multiple languages. The Other Contents business segment handles the website 'Gallery Japan', which operates Japanese traditional art crafts site. It also engages in the development and provision of online systems for the Internet and mobile phones; and planning & operation of software development and content delivery services. The company was founded by Daisuke Sekine on April 21, 1997 and is headquartered in Tokyo, Japan.