The Molino-Alexandrino-Radeschi Theorem establishes the smoothness of the leaf closure of a Riemannian foliation, that is, the partition of a manifold obtained by taking the closures of the leaves of a Riemannian foliation is itself a Riemannian foliation. In this talk, I will present this result and discuss the semi-local models of Riemannian foliations, which have a Lie-theoretic perspective and shed light on an alternative proof of the theorem. This is part of joint work with M. Alexandrino, M. Inagaki, and I. Struchiner.