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$Z^\prime$ models belong to the ones that can most easily explain theanomalies in $b\to s \mu^+\mu^-$ transitions. However, such an explanation by asingle $Z^\prime$ gauge boson, as done in the literature, is severlyconstrained by the $B^0_s-\bar B_s^0$ mixing. Also the recent finding, hat themass differences $\Delta M_s$, $\Delta M_d$, the CP-violating parameter$\varepsilon_K$, and the mixing induced CP-asymmetries $S_{\psi K_S}$ and$S_{\psi \phi}$ can be simultaneously well described within the SM without newphysics (NP) contributions, is a challenge for $Z^\prime$ models with a single$Z^\prime$ contributing at tree-level to quark mixing. We point out thatincluding a second $Z^\prime$ in the model allows to eliminate simultaneouslytree-level contributions to the five $\Delta F=2$ observables used in thedetermination of the CKM parameters while leaving the room for NP in $\DeltaM_K$ and $\Delta M_D$. The latter one can be removed at the price of infecting$\Delta M_s$ or $\Delta M_d$ by NP which is presently disfavoured. This patternis transparently seen using the new mixing matrix for $Z^\prime$ interactionswith quarks. This strategy allows significant tree-level contributions to $K$,$B_s$ and $B_d$ decays thereby allowing to explain the existing anomalies in$b\to s\mu^+\mu^-$ transitions and the anticipated anomaly in the ratio$\varepsilon'/\varepsilon$ much easier than in $Z^\prime$-Single scenarios. Theproposed $Z^\prime$-Tandem mechanism bears some similarities to the GIMmechanism for the suppression of the FCNCs in the SM with the role of the charmquark played here by the second $Z^\prime$. However, it differs from the latterprofoundly in that only NP contributions to quark mixing are eliminated attree-level. We discuss briefly the implied flavour patterns in $K$ and $B$decay observables in this NP scenario.

$Z^\prime$-Tandem Mechanism for the Suppression of New Physics in Quark Mixing with Implications for K, D and B Decays