The Sun emits time-varying magnetic fields, plasmas, and energetic particles. This solar variability drives changes in the interplanetary environment which then interacts with the Earth’s magnetic field and outermost atmosphere to produce changes in the near-Earth space environment. The space environment and its solar induced changes interact with spacecraft and instrument components and can cause anomalies resulting in loss of data, degradation of capability, service outages, and, in extreme cases, the loss of spacecraft. Space-based systems now provide critical infrastructure that support the quality of life on Earth. Because of humanity’s increasing dependence on space-based systems, spacecraft that can survive and operate through all space environment conditions are required. It is not possible to achieve cost-effective, “all weather” space systems without accurate knowledge of the space environment throughout all phases of mission development. The most effective time to prevent spacecraft anomalies is during the pre-launch phases of spacecraft development when taking the expected space “climate” into account and modifying technology selection and system designs to accommodate space environment effects can minimize risk. However, for most missions, some level of “residual risk” must be assumed due to cost constraints, increasing complexity of space systems, unknowns in the space environment, and/or unknowns in space environment effects mechanisms. Possible consequences of the residual risk on spacecraft health and safety and on degradation of service is evaluated and mitigated by bounding space weather conditions and writing appropriate operational guidelines for spacecraft operators.