Many tokamak plasma regimes have been developed which exhibitimproved plasma stability and energy confinement compared withthe ELMy H-mode which has been used for some time as thebaseline for reactor design. In particular, transient highperformance has been achieved in experiments with low orreversed magnetic shear (s = r/q(dq/sr)) and substantialprogress is now being made to extend these plasmas towardssteady state. The achievements with regime in several tokamakdevices are presented and outstanding issues for the furtherexploitation of this scenario are discussed.