Given the current state of research on replicable programs in education, it would be difficult to require that federal funds be limited to programs that have been rigorously evaluated, because there are so few such programs. However, programs that do have strong, rigorous evidence of effectiveness should be emphasized over those that are only based on valid principles, and there needs to be a strong effort to invest in development and evaluation of replicable programs in every area, so that eventually legislation can focus not on programs based on scientifically based research but on programs that have actually been successfully evaluated in rigorous experiments.