Symmetry- and spin-restricted self-consistent-field (SCF) theory by the basis-function expansion technique was first developed and implemented by C. C. J. Roothaan and coworkers at the University of Chicago [1, 2, 3]. They applied the theory principally to atoms [3, 4] and linear molecules [5, 6, 7] using Slater-orbital expansions. Applications to nonlinear molecules became very extensive once effective Gaussian-orbital integral programs [8, 9] and contraction techniques [10] were developed. The purpose of this review is to summarize this basic SCF theory in the form and extent used in SCFPQ [11], the SCF program module in the COLUMBUS suite of quantum chemistry programs [12].