tegies to assure successful system operation. Most system engineering activities rely upon component selection and derating to assure tolerance to mission integrated total ionizing and displacement damage dose effects. Similarly, destructive single event effects are prevented from occurring by selection of components or application conditions which prevent the occurrence of catastrophic single event effects. Single event upset and transient conditions are addressed by a spectrum of fault tolerance solutions; most of the specific techniques will be identified in section 6.0. The application of fault tolerance strategy requires knowledge of the effects, rate of occurrence, and the consequences which faults present to the operation of the system. Component testing, methods to estimate rate of occurrence, and knowledge of the dynamic nature of the environment with regard to the occurrence of faults are necessary to develop a fault tolerance strategy. Tolerance to Mission Integrated Effects [Kinnison98][Fleetwood95] Mission integrated effects on components and technologies used in space systems include total ionizing dose and displacement damage dose effects; description of these processes was briefly indicated in Section 4.1 and in-depth discussion has been provided in the other sections of this short course. Design and development activities directed towards assuring adequate tolerance to mission integrated effects consists of defining the environment external to the spacecraft, transport of the particle spectra and calculation of the mission integrated dose levels for component locations within the electronic assemblies, evaluating candidate devices and technologies for adequate tolerance and characterization of performance degradation, and establishing provisions which assure that adequate tolerance exists in the total population of devices to be used in systems. Figure 5-1 indicates the total ionizing dose levels versus equivalent aluminum shielding thickness for the geostationary and two low earth orbits. Appare