  The EFAR project is a study of 736 candidate elliptical galaxies in 84
clusters lying in two regions towards Hercules-Corona Borealis and
Perseus-Pisces-Cetus at distances cz = 6000-15000 km/s. In this paper (the
first of a series) we present an introduction to the EFAR project and describe
in detail the selection of the clusters and galaxies in our sample. Fundamental
data for the galaxies and clusters are given, including accurate new positions
for each galaxy and redshifts for each cluster. The galaxy selection functions
are determined using diameters measured from Schmidt sky survey images for 2185
galaxies in the cluster fields. Future papers in this series will present the
spectroscopic and photometric observations of this sample, investigate the
properties of the fundamental plane for ellipticals, and determine the
large-scale peculiar velocity fields in these two regions of the universe.
