Crystal Alliance
This division was created solely after the crystallization effect for humans was discovered. The captain and lieutenant of this squad will continue to be shinigami, but the seated members will actually be humans. This is to ensure a better alliance with the humans, as well as affect their crystallization, as well as train and control their abilities to assist in the detaining of hollowkind. Due to the physical presence of humans, this squad is actually based on earth, a secret area having been dug out under the Karakura City grocery store, of all places.

Command
This division is the head of Gotei 13 and the ones responsible for relaying Central 46 orders, dealing with Soul Society law and monitoring the other divisions.
The captain of the 1st Division is also the head of all other captains and the leader of Gotei 13, given the rank of General Commander.
Likewise, the 1st Division vice-captain is leader of the vice-captains and has authority over all vice-captains, next to their own captains and the General Commander.

Special Forces / Assassination & Undercover Operations
The captain of the 2nd Division is also captain of the Special Forces; one of Soul Society’s two other military fractions except for the Gotei 13.
Members of the 2nd Division are mainly dealing with stealth and assassination, and many of them are also members of the Special Forces as well. They also handle all undercover operations regarding Seireitei security

Intelligence & Information
The 3rd Division is the unit that are responsible of the act of sending out shinigami to gather information, and sometimes work in cooperation with 2nd Division agents on more serious missions. They are also the ones that sort all outgoing and incoming information before sending them to the 12th Division for storage .

Medical Assistance & Supply
The 4th Division deals with the brunt of the healing when it comes to shinigami or other spiritual entities. While the shinigami in this division use medicines for their healing, they do have the ability to use their energies for curative purposes, something unique to those that are in or have been in the 4th Division, because the average shinigami can only use their power for combat.
This unit is assigned many of the menial tasks in the Soul Society, such as cleaning the subterranean canals located under the Seireitei .

Seireitei Protection
The 5th Division is the ones that actually send out patrols on a daily, frequent basis to survey Seireitei. If a threat occurs, both 5th Division and the 13th Division are responsible for the defense of soul soceity.

Internal Affairs
The 6th Division handles all of Gotei 13’s internal affairs, such as monitoring shinigami activity and handling any disturbances from other shinigami. They are responsible for apprehending shinigami that breaks Soul Society laws and also detaining them until Division One has given their verdict in the matter.
Their division has the most holding cells, which is used to detain criminal offenders until they are judged.

Large-Scale Operations
The 7th Division is in charge of planning, coordinating, and executing large missions. Everything is run through their division first, and if approved, the 7th Division gathers the required shinigami from each division, assembles them, assigns duties, plans the attack, coordinate the shinigami according to the mission, execute the attack, and then keep maintenance over it. That includes sending out more reinforcements and information regarding the mission.

Reserves & Backup
The 8th Division is the mass reinforcement division. Their shinigami are split into groups that are talented in kidou, offensive tactics, or defensive tactics. When any of the other divisions require extra shinigami or reinforcements, the 8th is the division they turn to first.

Counter Intelligence
The 9th Division prevents information from leaking, as well as information being stolen. Their shinigami work close with the 12th Division research facility, to protect it from outside influence. They also prevent important information from leaking into Rukongai, especially information that could cause an uproar or mass panic.
Adding to this, they are also in charge of dealing with tactics and warfare against intelligent beings and massive hollow gatherings, and are the ones responsible for any counter tactics when Seireitei is under attack.
9th Division is also in charge of the memory-replacing that has to be done after shinigami fight in the living world

Seireitei-Rukongai Diplomacy
The 10th Division maintains peace between Seireitei and Rukongai. They make sure shinigami don’t go causing chaos in Seireitei, and are completely responsible for keeping Rukongai civil… or at least the area closest to Seireitei.
When souls have complaints/suggestions/questions/etc, whatever, they send is sent to the 10th Division where it is read, ignored, taken into consideration, and decided upon.

Offensive Tactics
The 11th Division is the frontlines. They are the most skilled in physical combat and work mainly with other divisions. During times of danger, the 11th Division is flooded out in mass numbers to immediately subdue problems, which include invasions of Seireitei

Research & Development
The 12th Division is in charge of gaining new information through experimentation. They research information that is sent to them from the third division before storing it.
They are also in charge of storing a mass amount of information known to Seireitei in their database. The 12th Division also develops new technology to aid shinigami in their missions.

Defensive Tactics
The 13th Division is the one who plan on defensive strategies in a battle. If the 5th Division send a report in there patrol about a danger they will immediately make a plan.
If a threat is a large enough, the 13th Division is in charge of sending out shinigami, assembling them, assigning them duties, and other things. Their job is similar to the 10th, except on a smaller basis.