  We study galaxy pairs in the field selected from the 100 K public release of
the 2dF galaxy redshift survey. Our analysis provides a well defined sample of
1258 galaxy pairs, a large database suitable for statistical studies of galaxy
interactions in the local universe, $z \le 0.1$. Galaxy pairs where selected by
radial velocity ($\Delta V$) and projected separation ($r_{\rm p}$) criteria
determined by analyzing the star formation activity within neighbours
(abridged). The ratio between the fractions of star forming galaxies in pairs
and in isolation is a useful tools to unveil the effects of having a close
companion. We found that about fifty percent of galaxy pairs do not show signs
of important star formation activity (independently of their luminosities)
supporting the hypothesis that the internal properties of the galaxies play a
crucial role in the triggering of star formation by interactions.
