Originally part of Masaya Games, a brand used by Nippon Computer Systems (NCS) or NCS Corporation, that became an independent studio while still working on the Langrisser game series.

They created Growlanser as a spiritual successor of Langrisser in 1999 which was published by Atlus.

In 2001, they were bought by and became a subsidiary studio of Atlus.

In 2004, most of the staff were merged into the main development team of Atlus and worked on the Devil Survivor sub-series of Shin Megami Tensei. Continuing to exist as a brand/label.

In 2010, Career Soft continued to exist as a brand/label after Atlus was bought by Index Corporation.

In 2013, Career Soft was dissolved into Sega Dream Corporation along with all other Index Corporation game assets when they were bought by Sega.

Sega Dream Corporation was renamed Index Corporation along with the merger.

In 2014, Index Corporation was split with it's business related departments were setup as a new Index Corporation while the games division was rebranded as Atlus.