A report is given of: (a) a substantial transport reduction by the turbulence driven E × B flows observed in three dimensional non-linear gyrokinetic simulations of microturbulence in magnetically confinedtoroidal plasmas; (b) an analytical derivation of the effective shearing rate for the time dependent E × B flow; (c) an interpretation ofexperimental data using linear gyrokinetic microinstability rotation models of E × B shear; (d) other developments in gyrokinetic theory and simulation.