The position of a second user (not the producing country) in Spare Parts Provisioning and the utilization of maintenance related provisioning models are studied in this thesis. A second user has to determine what his position is in the System Life Cycle, how much control he has over system life cycle cost, his needs with respect to spare part provisioning and what the crucial issues are. In the first part of the thesis, the concepts, activities and expenditures on these subjects are studied and modified from a second user's position. In the second part, two maintenance-related provisioning models (MDETRIC and OPUS) are described and compared. Finally, a sensitivity analysis utilizing the OPUS model was attempted for a hypothertical maintenance and support organization with supplemental data. Difficulties with the OPUS program precluded completion of this phase. (Author)