A data access control facility is implemented by assigning personally identifying information (PII) classification labels to PII data objects, with each PII data object having one PII classification label assigned thereto. The control facility further includes at least one PII purpose serving function set (PSFS) comprising a list of application functions that read or write PII data objects. Each PII PSFS is also assigned a PII classification label. A PII data object is accessible via an application function of a PII PSFS having a PII classification label that is identical to or dominant of the PII classification label of the PII object. A user of the control facility is assigned a PII clearance set which contains a list of at least one PII classification label, which is employed in determining whether the user is entitled to access a particular function.