Structural and electronic parameters of zincblende GaAs are obtained from density-functional-theory calculations utilizing an ab initio total energy pseudopotential technique within the local-density and the generalized gradient approximations. Detailed comparisons are made with the existing measured values and with results obtained in previous theoretical studies. The agreement between the present results and the available data from the literature is roughly satisfactory. Dependencies of some computed quantities on pressure are examined. (c) 2006 Elsevier Ltd. All rights reserved.