We discuss the prediction of $\frac{f_K}{f_{\pi }}$ that follows from chiral symmetry in the $(3, \overline{3})+(\overline{3}, 3)$ model from a general point of view. We present the results of the one-loop corrections in the renormalizable S${\mathrm{U}}_3$ $\sigma$ model. These results are compared with a number of other approaches, including chiral perturbation theory. All approaches discussed here have uncertainties in $\frac{f_K}{f_{\pi }}$ at least as large as, often much larger than, the experimental error in $\frac{f_K}{f_{\pi }}$. This is traced to the appearance of the mass difference ${m_{\eta }}^2-{m_K}^2$ which is uncertain to ±4% owing to isospin splitting.

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