Human being controlling the delivery of the treatment.

Stores SOP Instances (images, plans, structures, dose distributions, etc).

Manages worklists and tracks performance of procedures. This role is commonly filled by a Treatment Management System (Oncology Information System) in the Oncology Department. Acts as a UPS Pull SCP. The TMS has a user interface that may potentially be located in the treatment delivery control area. In addition, TMS terminals may be located throughout the institution.

Performs the treatment delivery specified by the worklist, updating a UPS, and stores treatment records and related SOP Instances such as verification images. Acts as a UPS Pull SCU. The TDS user interface is dedicated to the safe and effective delivery of the treatment, and is located in the treatment control area, typically just outside the radiation bunker.

Oversees and potentially inhibits delivery of the treatment. This role is commonly filled by a Treatment Management System in the Oncology Department, when the TDS is in the external verification mode. The MPV does not itself act as a UPS Pull SCU, but communicates directly with the TDS, which acts as a UPS Pull SCU. The MPV user interface may be shared with the TMS (in the treatment delivery control area), or could be located on a separate console.