The strong decay $\omega \to {\pi }^{+}{\pi }^{-}{\pi }^0$ and the photopion reaction $\gamma +\pi \to \pi +\pi$ are discussed using the hard-pion current-algebra technique. We use the anomalous Ward identities for three- and four-point functions to determine the structure of the contact term, but we are not able to determine it completely. Both the $\omega \to 3\pi$ and the $\gamma -3\mathrm{}\pi$ amplitude are then expressed in terms of three parameters $g_{\omega \rho \pi }$, $\xi$ (which characterizes the contact term), and $\delta$ (the parameter which appears in the $A_{1\rho \pi }$ system). We determine $g_{\omega \rho \pi }$ from a fit to the experimental $\omega \to {\pi }^0\gamma$ decay width and use this value of $g_{\omega \rho \pi }$ to determine the $\omega \to 3\pi$ width and the ratio $\Gamma \frac{(\omega \to {\pi }^0\gamma )}{\Gamma (\omega \to 3\pi )}$ for the various values of $\delta$, ignoring the contact term. Next we estimate $\xi$ by using the experimental decay width for $\omega \to 3\pi$ and use the resulting $\omega \to 3\pi$ amplitude to estimate $f_{\gamma -3\mathrm{}\pi }$. We also estimate the effect of anomalous Ward identities on the ${\pi }^0\to \gamma \gamma$ form factor and obtain the value of $F(0,0,0)\mathrm{}$ for $b_1=0\mathrm{}$ and $2b_1=3y$.

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