The mass density of stars in the Solar Neighbourhood is
a fundamental parameter in' Galactic Structure studies. We have
applied the method of photometric parallaxes (the M , (V-I))
relation ) to two complete samples of late-type dwarfs; one
selected from an objective prism survey, the other from COSMOS
photographic photometry of BVI UK Schmidt Telescope plates. The
resultant kinematically unbiased luminosity function shows that
the stellar number density peaks at M^ = +13 locally, falling off
very steeply thereafter. This result excludes hydrogen burning
stars brighter than M^ = +19 as significant contributors to any
local missing mass. We have also examined the kinematic selection
effects inherent in proper-motion based determinatio-ns of the
luminosity function, and show that high velocity halo stars
significantly affect results derived by this method. These effects
are substantial enough to permit an investigation of the local
subdwarf number density, which we find to be """CI. 4 percent that
of disk dwarfs. Finally, using UBVRIJHK photometry, we have applied
a blackbody fitting technique to derive temperatures and luminosities
for low luminosity dwarfs, and conclude that even the least luminous
are consistent with their interpretation as main sequence dwarfs
