The vast majority of known extrasolar planets orbit stars with a narrow range of masses (0.7-1.3 M_⊙). Little is known about the properties of planetary systems with host stars significantly more massive than the Sun. Planet formation models predict that giant planets are more common around higher-mass stars (M_* > 1.5M_⊙). However, these types of stars pose severe observational challenges while on the main sequence, resulting in a strong bias against them in current planet searches. Fortunately, it is possible to obtain high-precision Doppler velocities for these massive stars as they evolve off the main sequence and cool as sub-giants. We describe the Pan-Pacific Planet Search, a survey of 170 sub-giant stars using the 3.9m Australian Astronomical Telescope. In collaboration with J. Johnson's Keck survey of Northern "retired A stars," we are monitoring nearly every subgiant brighter than V = 8. This survey will provide critical statistics on the frequency and characteristics of planetary systems formed around higher-mass stars.
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