  Previously proposed procedure for improving the effective potential by using
renormalization group equation (RGE) is generalized so as to be applicable to
any system containing several different mass scales. If one knows L-loop
effective potential and (L+1)-loop RGE coefficient functions, this procedure
gives an improved potential which satisfies the RGE and contains all of the
leading, next-to-leading,..., and L-th-to-leading log terms. Our procedure here
also clarifies how naturally the so-called effective field theory can be
incorporated in the RGE in MS bar scheme.
