A shared spectrum manager (SSM) may enable spectrum access for Tier 2 Users (T2Us) and Tier 3 Users (T3Us) while provisioning quality of access (QoA) in a dynamic shared spectrum environment while ensuring sufficient spectrum and interference protection for Tier 1 Users (T1Us). The SSM may enable new user spectrum authorizations by sending, to a regulator, a request for administrative information, and receiving, from the regulator, a policy and user authorization information for at least one user. The SSM may register a T2U with or without contacting the regulator. The SSM may perform quality based admission control by receiving periodic measurements from a master device of each T2U with an active frequency assignment indicating a Quality of Operation (QoO) experienced by the respective T2U, maintaining a map of an effective QoOs for a plurality of T2Us, and categorizing protection contours associated with each of the plurality of T2Us.