Milestone A is a Milestone Decision Authority (MDA) led review at the end of the Materiel Solutions Analysis (MSA)Phase. Its purpose is to make a recommendation or seek approval to enter the Technology Development (TD) Phase. A milestone marks the start/or finish of a phase and has defined entrance and exit criteria.
A Major Defense Acquisition Program (MDAP) or Major Automated Information Support (MAIS) may not receive Milestone A approval until the Milestone Decision Authority (MDA) certifies, after consultation with the Joint Requirements Oversight Council (JROC) on matters related to program requirements and military needs, to the following, without modification, from 10 USC 2366a, as amended by Public law 111-23, "Weapon Systems Acquisition Reform Act of 2009", May 22, 2009: 
- That the program fulfills an approved Initial Capabilities Document (ICD);
- That the program is being executed by an entity with a relevant core competency as identified by the Secretary of Defense;
- An Analysis of Alternatives (AoA) has been performed consistent with the study guidance developed by the Director of Cost Assessment and Program Evaluation (DCAPE);
- An initial Life-Cycle Cost Estimate for the program has been submitted, with the concurrence of the Director of Cost Assessment and Program Evaluation (CAPE), and the level of resources required to develop and procure the program is consistent with the priority level assigned by the JROC; and
- [only include if the system duplicates a capability already provided by an existing system] the duplication provided by this system and (name of existing system) program is necessary to appropriate.
For MDAP at Milestone A, the MDA must certify in writing to the Congress that the Department has completed an Analysis of Alternative (AoA) consistent with study guidance developed by the DCAPE, in addition to meeting other certification criteria (10 U.S.C. 2366a).
Program Support Review
The Program Support Review (PSR) is conducted to provide insight into current and future program execution through detailed analysis using the Defense Acquisition Program Support (DAPS) Methodology. The Office of Secretary of Defense (OSD) Program Support Team applies the DAPS methodology to MDAP and MAIS programs approaching a Defense Acquisition Board (DAB) review. A PSR is designed to assist the Program Managers (PM) and systems engineer prepare for Milestone A, B, and C decision reviews.
For a list of mandatory items due at Milestone A, see the Milestone Requirements Matrix.
AcqLinks and References:
-  Defense Acquisition Guidebook (DAG) - Chapter 10.1.2.1
- DoD Directive 5000.01 "Defense Acquisition System" - 20 Nov 2007
- DoD Instruction 5000.02 "Operation of the Defense Acquisition System" - 26 Nov 2013
- DTM 09-027: Implementation of the Weapons System Acquisition Reform Act of 2009 (WSARA)
- DoD Template for Application of TLCSM and PBL
- DAU Glossary - 13th Edition
- Website: 10 USC § 2366a - Major defense acquisition programs"