alpha_S and Power Corrections from JADE

Re-analysed JADE data were used to determine alpha_S at sqrt{s} = 14-44 GeV on the basis of resummed calculations for event shapes and hadronisation models tuned to LEP data. The combined result is alpha_S(M_Z) = 0.1194 +/- 0.0082/0.0068 which is consistent with the world average. Event shapes have also been used to test power corrections based on an analytical model and to verify the gauge structure of QCD. The only non-perturbative parameter alpha_0 of the model was measured to alpha_0(2GeV) = 0.503 +/- 0.066/0.045 and is found to be universal within the total errors.