Employees are usually expected to participate to some extent in various nomikai, as it is considered a social aspect of work, although it is not expressly required.
Such parties focus on the bond between coworkers as a group, and are not considered private or somehow non-work related (see Japanese values).
At onset of the nomikai, the organizers give a brief welcome speech, followed by the manager, president, or principal, who offers words of reflection and encouragement.
Sometimes the shime (ending) may happen in conjunction with a verbose salute to the organizer or honored participant, or the singing of the company or school song.
After the main nomikai is concluded, the attendees often break into smaller groups and move to different bars.
As attendance is not at all mandatory for nijikai, they usually are groups of friends or people interested in doing a lot of drinking, including bar-hopping.
This is especially true of senpai-kōhai relationships, where the participant of lower rank or age will first offer to serve his superior.
Another point of etiquette which differs from Western business culture is that it is considered acceptable to become drunk at nomikai.