The paper considers the existence of the maximal possible hyperplane
partition of a continuous probability Borel measure in $\Bbb{R}^{4}$. The
emphases is on the use of the equivariant ideal valued index theory of
Fadell and Husseini. The presented result is the tightest positive solution
to one of the oldest and most relentless partition problems posed by B. Grünbaum~[12].
Keywords: Partition of measures; Fadell-Husseini index theory.