We investigate the influence that projection effects have on the completeness of the the Abell cluster catalogue in the context of an \Omega _ { 0 } = 1 CDM Universe .
We construct a galaxy catalogue and identify clusters using an algorithm that mimics Abell ’ s method .
Over 30 % of Richness Class \geq 1 clusters have been selected despite not meeting the required intrinsic ( 3D ) richness criterion .
Velocity dispersions are shown to have been systematically overestimated .