BRS invariance, asymptotic freedom and color confinement (a review)

It is proved that color confinement is an inevitable consequence of BRS invariance and asymptotic freedom inherent in quantum chromodynamics. BRS invariance is used to interpret or define color confinement and asymptotic freedom provides an essential means to prove it. It is also pointed out that introduction of renormalization is an essential step toward this proof and that renormalization group serves as the most useful tool in reaching the destination.