MIL-HDBK-881, DEPARTMENT OF DEFENSE HANDBOOK: WORK BREAKDOWN STRUCTURES FOR DEFENSE MATERIEL ITEMS (02 JAN 1998)., This handbook presents guidelines for effectively preparing, understanding, and presenting a Work Breakdown Structure (WBS). It is intended to provide the framework for Department of Defense (DoD) Program Managers to define their program?s WBS and also be valuable guidance to defense contractors in their application and extension of the contract?s WBS. Section 1 defines and describes the WBS. Section 2 provides instructions on how to develop a Program WBS in the pre-award timeframe. Section 3 offers guidance for developing and implementing a Contract WBS and Section 4 examines the role of the WBS in the post-award timeframe. This handbook also provides WBS definitions for specific defense materiel items in the Appendices.