The use of field programmable gate arrays (FPGAs) in satellite and other spacecraft is on the rise. They are increasingly competitive when compared to traditional application-specific integrated circuits (ASICs). However, exposure to space radiation produces the same physical effects on both FPGAs and ASICs. How these radiation effects can translate to circuit malfunctions and how these problems can be prevented or mitigated is a complex, multifaceted issue that depends on the specific technology and the device's internal architecture. First and foremost, designers should implement a reliable ASIC/FPGA development methodology for the definition, design, verification, physical implementation and validation phases of any ASIC/FPGA to be flown as part of the spacecraft platform or critical payload. This should be contractually enforced. The European Space Agency (ESA) will continue to make available its own internal standard or any other equivalent methodology proposed by the contractor. As soon as the new ECSS standard on this subject is available, ESA will start using it as an applicable document in all projects where ASICs or FPGAs are to be developed.