  We study vacua and walls of the mass-deformed nonlinear sigma model on the
Grassmann manifold $G_{N_F,N_C}=\frac{SU(N_F)}{SU(N_C)\times SU(N_F-N_C)\times
U(1)}$ and discuss three-pronged junctions for $N_C=1,2,3$ in four dimensions.
