A criteria-based sharing rule can identify Project records according to the Department field and share matching records with the appropriate public group. Salesforce documents that criteria-based sharing rules determine which records are shared based on field values and can grant access to public groups. Administrators can therefore maintain departmental public-group membership as employees change roles. When an employee leaves one department, removing that user from its public group removes the sharing path to those departmental Projects after sharing recalculation. Permission sets and profiles control object and field permissions but are not targets for criteria-based record-sharing rules. Account Teams apply specifically to Account collaboration and are unrelated to a custom Project object. With Project OWD set to Private, public groups plus criteria-based sharing provide the required controlled departmental visibility.

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