Integrated Master Schedule (IMS)/Integrated Master Plan (IMP) Application
Definition: The IMP is comprised of a hierarchy of program events, in which each event is supported by specific accomplishments, and each accomplishment is based on satisfying specific criteria to be considered complete. The IMS is an integrated, networked schedule containing all the detailed discrete work packages and planning packages (or lower level tasks of activities) necessary to support the events, accomplishments, and criteria of the IMP.
Keywords: earned value management, EVMS, integrated master plan, integrated master schedule, program plan, work breakdown structure, WBS
MITRE SE Roles & Expectations: The IMS and IMP form a critical part of effectively providing acquisition support. MITRE systems engineers (SEs) should understand the use and implementation of these tools and how they can be used to effectively monitor program execution.
What We Know About the IMS and IMP
Program planning involves developing and maintaining plans for all program processes, including those required for effective program office-contractor interaction. Once the contract is signed and schedule, costs, and resources from the contractor are established, the program plan takes into account, at an appropriate level of detail, the contractor's estimations for the program. Together, the IMP and IMS should clearly demonstrate that the program is structured and executable within schedule and cost constraints with an acceptable level of risk. During the proposal evaluation and source selection phases, the IMP and IMS are critical components of the offeror's proposal; they identify the offeror's ability to partition a program into tasks and phases that can be successfully executed to deliver the proposed capability. After contract award, the IMP and IMS are used by the contractor and/or the government as the day-to-day tools for executing the program and tracking program technical and schedule status, including all significant risk mitigation efforts.
The IMP and IMS are business tools to manage and provide oversight of acquisition, modification, and sustainment programs. They provide a systematic approach to program planning, scheduling, and execution. They are equally applicable to competitive and sole source procurements with industry, as well as to government-only, in-house efforts. They help develop and support program/project budgeting, and can be used to perform "what-if" exercises and to identify and assess candidate problem workarounds. Finally, use of the IMP/IMS focuses and strengthens the interaction between the government and contractor teams with respect to program execution.
Best Practices and Lessons Learned
Right Type and Level of Detail: The IMP should provide sufficient definition to track the step-by-step completion of the required accomplishments for each event, and to demonstrate satisfaction of the completion criteria for each accomplishment. Events in the IMP are not tied to calendar dates; they are tied to the accomplishment of a task or work package as evidenced by the satisfaction of the specified criteria for that accomplishment. The IMS should be defined to the level of detail necessary for day-to-day execution of the program.
To build a reasonable IMP and IMS, you need to estimate the attributes of work products and tasks, determine the resources needed, estimate a schedule, and identify and analyze program risks. Accomplishments in the IMP should have criteria for determining completion with clear evidence so that the entire program team can understand the progress. The IMS and IMP should be traceable to the work breakdown structure (WBS), and be linked to the statement of work and ultimately to the earned value management system (EVMS). The WBS specifies the breakout of work tasks that the IMP and IMS should be built on and the EVMS should report on. A good WBS includes key work efforts partitioned into discrete elements that result in a product (i.e., document, software item, test completion, integrated product) or in measurable progress (percent complete is not recommended when the end state is not completely quantifiable—an issue in software development, test procedures, or training materials). With a good WBS foundation, both the IMP and IMS can be more useful tools; with the IMP integrating all work efforts into a defined program plan, and the IMS summarizing the detailed schedule for performing those work efforts. The IMP is placed on contract and becomes the baseline execution plan for the program/project. Although fairly detailed, the IMP is a relatively top-level document compared to the IMS. The IMS should not be placed on contract; it is normally a contract-deliverable.
For evaluating a proposed IMS, focus on realistic task durations, predecessor/successor relationships, and identification of critical path tasks with viable risk mitigation and contingency plans. An IMS summarized at too high a level may often result in obscuring critical execution elements, and contributing to failure of the EVMS to accurately report progress (for more details on EVMS, refer to the article on Acquisition Management Metrics in this section). A high-level IMS may also fail to show related risk management approaches being used, which often results in long duration tasks and artificial linkages masking the true critical path.
An example of this is an IMS with several concurrent activities progressing in parallel and showing a critical path along one activity that later links and transitions to another activity. A third activity also shows a dependency to the first, but it is not considered to be on the critical path. If the IMS does not have the detail to determine the progress point at which the critical path transitions to the second activity, the real critical path could be along the dependency of the third activity. Conversely, an IMS that is too detailed may also result in similar problems; the critical path is too hard to identify (looking in the weeds instead of up at the trees). The physical maintenance of the IMS becomes tedious and linkages could be missed in the details. An IMS ends up being ineffective on a program when it is either too high level or too detailed.
In general, the IMP can be thought of as the top-down planning tool and the IMS as the bottom-up execution tool for those plans. It should be noted, however, the IMS is a scheduling tool for management control of program progression, not for cost collection purposes.
Measurable Criteria: Criteria established for IMP accomplishments should be measurable (i.e., satisfactory completion of a test event, approval of a study report, or verification of an activity or test). Consider including accomplishment of critical performance requirements (key performance parameters or technical performance metrics). For these, it important to link criteria to the specification versus the actual performance requirement embedded in the criteria so requirements do not have to be maintained in more than one document.
Multiple Delivery/Increment Programs: On programs with multiple deliveries and/or multiple increments, ensure that the IMS includes cross-delivery order and cross-increment relationships. This is valuable when conducting critical path analyses on the IMS. These relationships sometimes drive "ripple effects" across the delivery orders and work tasks, and when analyzing a critical path or estimating a "what if" or total cost for a modification, this is an extremely valuable factor.
Stakeholder Involvement: Relevant stakeholders (including user organizations, financial managers, and sustainment organizations) should be involved in the planning process from all life-cycle phases to ensure that all technical and support activities are adequately addressed in program plans such as the IMP and IMS.
Communicating via IMS: The IMS can be used to communicate with stakeholders on a regular basis. For enterprise systems with large numbers of external interfaces and programs, the IMS can be used as the integration tool to indicate and track milestones relevant to the other programs.
References & Resources
- Acquisition Community Connection, Integrated Master Plan (IMP)/Integrated Master Schedule (IMS), accessed June 8, 2010.
- AFMC Pamphlet 63-5, November 11, 2004, Integrated Master Plan and Schedule Guide.
- Department of Defense, October 21, 2005, Integrated Master Plan and Integrated Master Schedule: Preparation and Use Guide, version 0.9.
- Duquette, J., November 30, 2006, IMP/IMS Overview
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