We give a unified approach to localization of maximally symmetric gauge theories on spheres, including S 6 and S 7 . The approach follows Pestun's method of dimensionally reducing from 10 dimensional super Yang-Mills. The resulting theories have a reduced R-symmetry which includes an SU(1, 1) subgroup, except in four dimensions where, because of conformal invariance, the full flat-space R-symmetry is maintained, and in seven dimensions where SU(1, 1) is the flat-space R-symmetry. For the case of S 6 and S 7 we discuss the localization of these theories and also present new results for the corresponding matrix models. The matrix models for S 6 and S 7 are qualitatively similar to the matrix models of a vector multiplet on S 4 and S 5 respectively. We also discuss the contributions of instantons in the six and seven dimensional cases.