Heavy-light and light-light weak matrix elements on the lattice

I review recent developments in lattice weak matrix element calculations. I focus on on $f_B$ (both with propagating quarks and in the static limit for the $b$ quark), semi-leptonic form factors for $D$ meson decay, form factors for $B \to K^* \gamma$, and $B_K$. [Review presented at Lattice '93]