A general technique for proving the irrationality of the zeta constants ζ(2n + 1), n ≥ 1, from the known irrationality of the beta constants L(2n + 1, χ) is developed in this note. The irrationality of the zeta constants ζ(2n), n ≥ 1, and ζ(3) are well known, but the irrationality results for the zeta constants ζ(2n + 1), n ≥ 2, are new, and seem to show that these are irrational numbers. By symmetry, the irrationality of the beta constants L(2n, χ) are derived from the known rrationality of the zeta constants ζ(2n).