The luminosity function of solar-neighborhood OB stars is derived from a sa
mple of nearly 2600 such objects brighter than m(pg) = 10 via a method that
makes use of varying completeness-to-distance estimates depending on the a
bsolute magnitudes of the sample members and their (assumed) exponential de
nsity distribution perpendicular to the Galactic plane. The derived luminos
ity function is in good agreement with that published previously by Humphre
ys and McElroy over the range -7 < M-v < -4. The integrated Galactic plane
density of OB stars within this range of absolute magnitudes is estimated a
t 9.1 x 10(-7) stars pc(-3), and the total number of OB stars within the so
lar circle is estimated at similar to 19,000. The predicted number of OB st
ars more massive than 20 solar masses within 2.5 kpc of the Sun, 636, is 50
% greater than the value of 424 given earlier by Germany et al., indicating
that their sample was not as complete as they had assumed.