Milestone (MS) - The point at which a recommendation is made and approval sought regarding starting or continuing an acquisition program, i.e., proceeding to the next phase. Milestones established by DoDI 5000.2 are: MS A that approves entry into the Technology Development (TD) phase; MS B that approves entry into the System Development and Demonstration (SDD) phase; and MS C that approves entry into the Production and Deployment (P&D) phase. Also of note are the Concept Decision (CD) that approves entry into the Concept Refinement (CR) phase; the Design Readiness Review (DRR) that ends the System Integration (SI) effort and continues the SDD phase into the System Demonstration (SD) effort; and the Full Rate Production Decision Review (FRPDR) at the end of the Low Rate Initial Production (LRIP) effort of the P&D phase that authorizes Full Rate Production (FRP) and approves deployment of the system to the field or fleet. 2. In the context of scheduling, a specific definable accomplishment in the contract network that is recognizable at a particular point in time. Milestones have zero duration, do not consume resources, and have defined entry and exit criteria. A milestone may mark the start and/or finish of an interim step, event, or program phase. (Government-Industry Earned Value Management Working Group)