## Considerations for dynamic membership groups
When the attributes of a user or a device change, the system evaluates all rules for dynamic membership groups in a directory to see if the change would trigger any group adds or removes. If users or devices satisfy a rule on a group, they're added as members of that group. If they no longer satisfy the rule, they're removed. You can't manually add or remove a member of a dynamic membership group.
Also keep these limitations in mind:
### License requirements
The feature of dynamic membership groups requires a Microsoft Entra ID P1 license or an Intune for Education license for each unique user who is a member of one or more dynamic membership groups. You don't have to assign licenses to users for them to be members of dynamic membership groups, but you must have the minimum number of licenses in the Microsoft Entra organization to cover all such users.
For example, if you have a total of 1,000 unique users in all dynamic membership groups in your organization, you need at least 1,000 licenses for Microsoft Entra ID P1 to meet the license requirement.
Microsoft Entra ID provides a rule builder to create and update your important rules more quickly. The rule builder supports the construction of up to five expressions. You can use the rule builder to form a rule with a few simple expressions, but you can't use it to reproduce every rule. If the rule builder doesn't support the rule that you want to create, you can use the text box.
> [!IMPORTANT]
> The rule builder is available only for user-based dynamic membership groups. You can create device-based dynamic membership groups only by using the text box.
## Considerations for dynamic membership groups
When the attributes of a user or a device change, the system evaluates all rules for dynamic membership groups in a directory to see if the change would trigger any group additions or removals. If users or devices satisfy a rule on a group, they're added as members of that group. If they no longer satisfy the rule, they're removed. You can't manually add or remove a member of a dynamic membership group.
Also keep these limitations in mind:
### License requirements
The feature of dynamic membership groups requires a Microsoft Entra ID P1 license or an Intune for Education license for each unique user who's a member of one or more dynamic membership groups. You don't have to assign licenses to users for them to be members of dynamic membership groups. But you must have the minimum number of licenses in the Microsoft Entra organization to cover all such users.
For example, if you have a total of 1,000 unique users in all dynamic membership groups in your organization, you need at least 1,000 licenses for Microsoft Entra ID P1 to meet the license requirement.
Microsoft Entra ID provides a rule builder to create and update your important rules more quickly. The rule builder supports the construction of up to five expressions. You can use the rule builder to form a rule with a few simple expressions, but you can't use it to reproduce every rule. If the rule builder doesn't support the rule that you want to create, you can use the text box.
:::image type="content" source="./media/groups-dynamic-membership/update-dynamic-group-rule.png" alt-text="Screenshot that shows the rule builder, with the action for adding an expression highlighted.":::
For step-by-step instructions, see [Create or update a dynamic membership group](groups-create-rule.md).