  Let $M$ be a Riemannian manifold of dimension $n+1$ with smooth boundary and
$p\in \partial M$. We prove that there exists a smooth foliation around $p$
whose leaves are submanifolds of dimension $n$, constant mean curvature and its
arrive perpendicular to the boundary of M, provided that $p$ is a nondegenerate
critical point of the mean curvature function of $\partial M$.
