Measurements of the combined branching ratios for $B^\pm \to \pi^\pm K$ and
$B_d \to \pi^\mp K^\pm$ allow interesting constraints on the CKM angle
$\gamma$, the ratio $r \equiv |T'|/|P'|$ of the current-current and penguin
operator contributions to $B_d \to \pi^\mp K^\pm$, and the CP asymmetry
in that decay. Present CLEO results for these branching ratios indicate
where problems with consistency of the Standard Model may arise in the
future. In this paper we discuss scenarios of new physics in these decays
and investigate their implications for the above constraints.