This paper is concerned with a Kantorovich variant of the Meyer-Konig and Zeller operators which was defined by Maier, Muller and Swetits. We derive sharp bounds for the first and second central moments yielding estimates for the rate of convergence in terms of the modulus of continuity. Finally, we study the asymptotic behaviour of these operators. Mathematics subject classification (2000): 41A25, 41A36, 41A60.