The Integrated Master Schedule (IMS) is a time-based schedule containing the networked, detailed tasks necessary to ensure successful program/contract execution. The IMS is traceable to the Integrated Master Plan (IMP), Work Breakdown Structure (WBS), Statement of Work (SOW), Contractor Performance Report (CPR) and Earn Value Management system (EVMS).
The IMS is used to verify attainability contract objectives, evaluate progress toward meeting program objectives, and integrate the program schedule activities with all related components. The Program Manager (PM) develops an IMS on all cost or incentive contracts, subcontracts, Government Interagency Acquisition work agreements, and other agreements valued at or greater than $20 million. 
The IMS utilizes Critical Path network management techniques to optimize the relationship of critical activities. It uses the same (3) three; Events, Accomplishments, and Criteria to show network relationships; as IMP.
Definition: The Integrated Master Schedule (IMS) is a time-based schedule containing the networked, detailed tasks necessary to ensure successful program/contract execution.
The 4 Steps to Developing an Integrated Master Schedule (IMS): 
- Step 1: Develop the Integrated Master Plan (IMP)
- Step 2: Develop the Work Breakdown Structure (WBS) based on the overall system’s Physical Architecture identifying all of the major systems and subsystems down to a configuration item level (CI)
- Step 3: Defined configuration item level in terms of calendar time and resources to complete
- Step 4: Place developed system time and resources into scheduling software (see Schedule Development)
IMS Contract Data Requirements List (CDRL)
Data Item Description DI-MGMT-81661 “Integrated Program Management Report (IPMR
How the Integrated Master Plan (IMP) relates to the Integrated Master Schedule (IMS)
The IMP and Integrated Master Schedule (IMS) are linked together and show that a program is adequately planned and has the potential to achieve its goals and objectives within a program’s schedule and cost constraints. The IMP and IMS are valuable tools a PM can use in preparing for a Request for Proposal (RFP) and Source Selection. It can serve as the basis of an offeror’s proposal and evaluation criteria.
The IMP and IMS are Program Management tools for program personnel and stakeholders to provide oversight of acquisition programs. They provide a systematic approach to program planning, scheduling, and execution.
AcqLinks and References:
-  Defense Acquisition Guidebook (DAG)
- DoD Integrated Master Plan and Integrated Master Schedule Preparation and User Guide