  The stability of strange pentaquarks $uudd\bar s$ is studied in a constituent
quark model based on a flavor-spin hyperfine interaction between quarks. With
this interaction model, which schematically represents the Goldstone boson
exchange interaction between constituent quarks, the lowest lying strange
pentaquark is a $p-$shell state with positive parity. The flavor-spin
interaction lowers the energy of the lowest $p-$shell state below that of the
lowest $s-$shell state, which has negative parity because of the negative
parity of the strange antiquark. It is found that the strange pentaquark is
stable against strong decay provided that the strange antiquark interacts by a
fairly strong spin-spin interaction with $u$ and $d$ quarks. This interaction
has a form that corresponds to $\eta$ meson exchange. Its strength may be
inferred from the $\pi^0$ decay width of $D_s^*$ mesons.
