Expressions are derives for the yawing derivatives on the assumptions of the linearised theory of flow for a delta wing with small dihedral flying at supersonic speeds at small incidences. The non-dimensional derivatives are numerically decreasing functions of Mach number. The non-dimensional rolling and yawing derivatives are also numerically decreasing functions of aspect ratio. When the wing lies entirely within the apex Mach cone there is a leading edge suction force proportional to incidence which makes a destabilising contribution to the yawing moment and side force which may be of the same magnitude as that from the inducted excess pressure distribution.