We try to understand the strangeness changing nonleptonic decays of kaons, hyperons, and the Ω− particle in terms of the modern, renormalized weak Hamiltonian expressed as a sum of four-quark Wilson operators, including the so-called penguin operators c5O5 and c6O6 arising from gluon radiative corrections. It is found that these decays, including the long-standing s-wave/p-wave puzzle in hyperon decays, can be understood if the Wilson coefficient has a sign opposite to that obtained from short-distance perturbative quantum chromodynamics calculations and has an effective value such that .