Moodle core provides a mechanim to manually fill cohorts with users (on Site administration -> Users -> Accounts -> Cohorts). This is fine for small Moodle installations where the cohort members don't change too often and where the Moodle admin has plenty of time to update the cohorts.

Now, larger or fragmented Moodle installations may have the need to manage a large number of cohorts which have a large amount of members and which may also change quite often. Managing cohorts by hand in such scenarios is simply unprofessional overkill - even / particularly if you distribute the work among multiple Moodle admins.

On the other hand these large or fragmented Moodle installations might already have some custom user profile fields which can be leveraged to decide which cohort(s) a user should be a member of. This plugin implements a simple solution to manage cohort memberships based on a users' custom profile field.

Please see README file for details about the usage and features of this plugin.