  We present key sample results of a systematic survey of the pulsation
properties of models of hot B subdwarfs. We use equilibrium structures taken
from detailed evolutionary sequences of solar metallicity (Z = 0.02)
supplemented by grids of static envelope models of various metallicities (Z =
0.02, 0.04, 0.06, 0.08, and 0.10). We consider all pulsation modes with l = 0,
1, 2, and 3 in the 80--1500 s period window, the interval currently most
suitable for fast photometric detection techniques. We establish that
significant driving is often present in hot B subdwarfs and is due to an
opacity bump associated with heavy element ionization. We find that models with
Z >= 0.04 show low radial order unstable modes; both radial and nonradial (p,
f, and g) pulsations are excited. The unstable models have Teff > 30,000 K, and
log g > 5.7, depending somewhat on the metallicity. We emphasize that metal
enrichment needs only occur locally in the driving region. On this basis,
combined with the accepted view that local enrichments and depletions of metals
are common place in the envelopes of hot B subdwarfs, we predict that some of
these stars should show luminosity variations resulting from pulsational
instabilities.
