National Aeronautics and Space Administration (NASA). This Technical Handbook approved by NASA February 17, 1999. 53 p. This document establishes guidelines and design practices to be used by NASA and other spacecraft designers to minimize the detrimental effects of spacecraft internal charging. These effects are due to interactions between the in-flight plasma environment and spacecraft electronic systems. The detrimental effects are disruption or damage from electrostatic discharges (ESD’s) at interior regions of the spacecraft that may be charged by space plasmas. The handbook applies to any spacecraft whose circular Earth orbit is described by the labeled regions of Figure 1, as well as other energetic plasma environments such as at Jupiter. Designs for spacecraft with orbits in these regions should be examined for the threat from internal charging.