The Dual QCD (DQCD) framework, based on the ideas of t Hooft and Witten, and developed by Bill Bardeen, Jean-Marc Gerard and myself in the 1980s is not QCD, a theory of quarks and gluons, but a successful low energy approximation of it when applied to $Ktopipi$ decays and $K^0-bar K^0$ mixing. After years of silence, starting with 2014, this framework has been further developed in order to improve the SM prediction for the ratio $epsilon/epsilon$, the $Delta I=1/2$ rule and $hat B_K$. Most importantly, this year it has been used for the calculation of all $Ktopipi$ hadronic matrix elements of BSM operators which opened the road for the general study of $epsilon/epsilon$ in the context of the SM effective theory (SMEFT). This talk summarizes briefly the past successes of this framework and discusses recent developments which lead to a master formula for $epsilon/epsilon$ valid in any extension of the SM. This formula should facilitate the search for new physics responsible for the $epsilon/epsilon$ anomaly hinted by 2015 results from lattice QCD and DQCD.
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