The 3rd Division is said to be based on Psychological warfare. Manning the Senkaimon gate and in charge of the restricted archives that contain forbidden Kidou along with history and information not meant for most eyes. The Sanbantai may be sent to carry out missions, that could give a physiological advantage to the Gotei 13. This is there speciality. Being responsible for manning the Senkaimon Gate. The Sanbantai also keeps records, along with the 12th Division. These documents are stored inside books and databases, should a situation arise where such records are needed.
Real World Reconnaissance, finding missing Shinigami that have gone to the real world and have become missing or undetectable. Usually their missions consist of bringing Shinigami back who have had prolonged period missions in the Human World. The Rokubantai are also known for policing the Seireitei. Members of the Rokubantai will often detain those who have broken the law, so that they may be brought to justice.
The mission of the Ninth Division is to protect the Seireitei. It is always on standby for combat because it is the security force of the Gotei 13. Traditionally, Ninth Division has overseen arts and culture. For this reason it is known to be in charge of the Seireitei news magazine. All the lieutenants of the divisions of Gotei 13 hand in their reports to them.
The 12th Division develops new technology and spiritual tools and is the home of the S.R.D.I, founded by Kai. As such technological and scientific research has become the full measure of what the division involves itself in primarily. Members are tasked with research and collection of data and samples. The 12th division is also responsible for monitoring the material world, reporting back any disturbances that may prove to be a threat. The 12th Division keeps a constant eye on the Material World and even the Seireitei as a whole.