It was established in June 2002 as a branch of Computer Entertainment Supplier's Association, and became an officially recognized nonprofit organization under Japanese law in December 2003.

The symbols that CERO uses are stylized Latin letters, named after academic grading, except "F" is replaced with "Z".

(Bar colors: black for "A"; green for "B"; blue for "C"; orange for "D"; red for "Z") In April 2004, CERO defined the following "content icons".

According to Kazuya Watanabe, CERO's senior director, the group of assessors is composed of five regular people unaffiliated with the game industry.

[7] In a 2015 compilation of columns that he wrote for Famitsu magazine, video game developer and Super Smash Bros. series creator Masahiro Sakurai criticized CERO for having stricter standards on sexual content than violence, citing conflicts that he had with the board over the character models for Palutena and Wonder Pink in Super Smash Bros. for Nintendo 3DS and Wii U.

According to Sakurai, the game was nearly delayed due to the developers needing to constantly revise the characters' models, which CERO considered "sexually provocative" due to the possibility that players could take upskirt shots with them.

Sakurai claimed that these designs were never intended to be titillating, deriding CERO's demands as "ridiculous and frankly quite juvenile.