  The strange sea of the proton is generally assumed to have quark - antiquark
symmetry. However it has been known for some time that non-perturbative
processes involving the meson cloud of the proton may break this symmetry.
Recently this has been of interest as it affects the analysis of the so-called
`NuTeV anomaly', and could explain the large discrepancy between the NuTeV
measurement of $\sin^{2} \theta_{W}$ and the currently accepted value. In this
paper we re-examine strange - anti-strange asymmetry using the meson cloud
model. We calculate contributions to the strange sea arising from fluctuations
in the proton wavefunction to states containing either Lambda or Sigma hyperons
together with either Kaons or pseudovector $K^{*}$ mesons. We find that we
should not ignore fluctuations involving $K^{*}$ mesons in this picture. The
strange sea asymmetry is found to be small, and is unlikely to affect the
analysis of the Llewellyn-Smith cross section ratios or the Paschos-Wolfenstein
relationship.
