Up to this point we have discussed the impacts of configuration and reaction conditions on the CO2 reduction reaction and vice versa. While understanding the CO2 reduction reaction and catalyst over a range of conditions is important, our preferred choice of catalyst and catholyte will have implications and constraints for the system as a whole. Further catalyst testing in a more commercial-type reactor will help to bring operational issues to the forefront of the field and may result in new ingenious scientific and engineering solutions to these issues.