Two chiral-symmetry-breaking schemes are considered within the context of a linear SU(3) $\sigma$ model. In the first the symmetry-breaking terms are constructed from the usual linear (in the fields) (3,$3^{*}$) ⊕ ($3^{*}$,3) contribution together with bilinear combinations belonging to the (6,$6^{*}$) ⊕ ($6^{*}$,6) representation of SU(3) X SU(3). In the second scheme a combination of linear and bilinear (3,$3^{*}$) ⊕ ($3^{*}$,3) terms is employed. The pseudoscalar mesons ($\pi ,K,\eta ,{\eta }^{\prime }$) and scalar mesons ($\epsilon ,\kappa ,\sigma ,{\sigma }^{\prime }$) are assigned to the (3,$3^{*}$) ⊕ ($3^{*}$,3) representation in this model which is used to describe their mass spectra, various scalar meson decays, ${\eta }^{\prime }\to \eta \pi \pi$, and the $\pi \pi$ and $\pi K$ scattering lengths. With the addition of isospin-violating terms to the Lagrangian additional, electromagnetic effects can be taken into account. In each of the symmetry-breaking schemes considered it is found that a two-parameter form in which the linear (3,$3^{*}$) ⊕ ($3^{*}$,3) contribution is SU(2) X SU(2)-invariant and the bilinear contribution is SU(3)-invariant is about as successful as the usual two-parameter linear (3,$3^{*}$) ⊕ ($3^{*}$,3) form.

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