  A new quantum spin model with frustration, the `Union Jack' model on the
square lattice, is analyzed using spin-wave theory. For small values of the
frustrating coupling $\alpha$, the system is N{\' e}el ordered as usual, while
for large $\alpha$ the frustration is found to induce a canted phase. The
possibility of an intermediate spin-liquid phase is discussed.

Strongly Correlated Electrons;Statistical Mechanics