  As a result of the interplay between the intrinsic off-diagonal terms of the
dipolar interaction and an applied {\it transverse} field $H_t$, the diluted
${\rm LiHo_xY_{1-x}F_4}$ system at x$> 0.5$ is equivalent to a ferromagnet in a
longitudinal random field (RF). At low $H_t$ the quantum fluctuations between
the Ising like doublet states are negligible, while the effective induced RF is
appreciable. This results in a practically exact equivalence to the classical
RF Ising model. By tuning $H_t$, the applied longitudinal field, and the
dilution, the Ising model can be realized in the presence of an effective RF,
transverse field, and constant longitudinal field, all independently
controlled. The experimental consequences for $D=1,2,3$ dimensions are
discussed.
