Note: The Life-Cycle Signature Support Plan (LSSP) has been replaced by the Life-Cycle Mission Data Plan (LMDP) effective 22 January 2013.
A Life-Cycle Signature Support Plan (LSSP) is required for validated and approved signature-dependent programs. A signature-dependent program is a defense acquisition that uses or is comprised of a sensor, system, or process that relies on signatures or signature data to successfully perform a task or mission. An LSSP should be included in the Technology Development Strategy (TDS) and developed during the Materiel Solution Analysis (MSA) Phase and Technology Development (TD) Phases and should fully be defined prior to Milestone B. 
Template: Life-Cycle Signature Support Plan (LSSP)
Life-Cycle Signature Support Plan (LSSP) Definition
A management plan that is applied throughout the life of a signature-dependent acquisition that bases all programmatic decisions on the anticipated mission-related and economic benefits derived over the life of a signature-dependent acquisition. 
The TDS should describe signature support requirements and required funding to support program-related efforts. The requirements and required funding should be developed in concert with the Intelligence Community and the Senior Signature Management Forum. If the LSSP needs to be classified to fulfill the information required it should be so noted in the unclassified TDS and a classified LSSP annex of the TDS should be handled separately. 
Applicable acquisition programs need to identify, capture and address the signatures essential to the development, testing, fielding, operation, and maintenance of required weapons, smart munitions, sensors, and systems capabilities at each program Milestone and prior to proceeding to the Low-Rate Initial Production (LRIP).
AcqLinks and References:
-  Defense Acquisition Guidebook (DAG) – Chapter 2
-  DoD Directive 5250.01 Management of Intelligence Mission Data (IMD) in DoD Acquisition – 22 Jan 13