Operations and Support (O&S) Phase Site problems The purpose of the O&S Phase is to execute a support program that meets materiel readiness and operational support performance requirements, and sustains the system in the most cost-effective manner over its total life cycle. Planning for this phase begins prior to program initiation and is documented in the Life Cycle Sustainment Plan (LCSP). O&S has two major efforts; 1. Life Cycle Sustainment 2. Disposal Entrance into the O&S Phase depends on meeting the following criteria: • An approved Capabilities Production Document (CPD) • An Approved LCSP • A successful Full-Rate Production (FRP) decision