  We analyse the environment of low redshift, z < 0.2, SDSS quasars using the
spectral and photometric information of galaxies from the Sloan Digital Sky
Survey Third Data Release (SDSS-DR3). We compare quasar neighbourhoods with
field and high density environments through an analysis on samples of typical
galaxies and groups. We compute the surrounding surface number density of
galaxies finding that quasar environments systematically avoid high density
regions. Their mean environments correspond to galaxy density enhancements
similar to those of typical galaxies. We have also explored several galaxy
properties in these environments, such as spectral types, specific star
formation rates, concentration indexes, colours and active nuclei activity. We
conclude that low redshift quasar neighbourhoods (r_p < 1 Mpc h^-1, Delta V <
500 km/s) are populated by bluer and more intense star forming galaxies of
disk-type morphology than galaxies in groups and in the field. Although star
formation activity is thought to be significantly triggered by interactions, we
find that quasar fueling may not require the presence of a close companion
galaxy (r_p < 100 kpc h^-1, Delta V< 350 km/s). As a test of the unified AGN
model, we have performed a similar analysis to the neighbours of a sample of
active galaxies. The results indicate that these neighbourhoods are comparable
to those of quasars giving further support to this unified scenario.
