KAON WEAK INTERACTIONS IN POWERS OF 1/N_C

I review a recent analytic method for computing matrix elements of electroweak operators based on the large-N_c expansion. In particular, I give a rather detailed description of the matching of the quark Lagrangian onto the meson chiral Lagrangian governing mixing. In the ΔS = 1 sector, I explain how to obtain an estimate for both ε′/ε and the ΔI = 1/2 rule. Finally, I give an example of how the method can also be useful for lattice calculations.