With the Business Plan, you can enable the Require Agreement feature in your workspace settings.
The agreement is fully customizable and will appear the first time a user enters a workspace. If the agreement is enabled after a workspace has been created, all users already invited to the workspace will have to accept the agreement the next time they access the workspace. When a user accepts the agreement, they will be allowed to enter the workspace and the Activity Log will reflect that the user has accepted the agreement. If a user declines, they will not be allowed to enter the workspace until they accept the agreement.