A computerized method for allowing multiple applications to create groups in a common address book while maintaining control over access to the created group. A creating application creates a group within a shared address book and may provide access logic for access to the group. Additional applications may then send a request to an intermediary component such as an Application Program Interface ("API") for access to the group. The API determines if there is access logic to execute. If there is no logic, access may be granted to the group. If there is access logic, then the logic is executed and access is granted or denied depending on the prerequisites for access found in the logic.