A clone library of 11 of 15 BamHI fragments representing 81% of the 140 kilobase DNA genome of the prototype bovine encephalitis herpesvirus strain N569 (BEHV.N569) was constructed. The clones were used to verify the BamHI, BstEII, EcoRI, and HindIII genomic maps for BEHV.N569 published by Engels et al. [Virus Res 6: 57-73 (1986)] for the same virus although some amendments/variations to the BamHI map were found in that 3 previously unidentified restriction sites were identified. Restriction site maps for BglII and KpnI were also derived for BEHV.N569. Southern blot analysis using 32P-labelled BEHV DNA as probe indicated that bovine herpesvirus 1 (BHV1), buffalo herpesvirus 1 (BuHV1) and caprine herpesvirus 1 (CaHV1) were similar and that the similarity occurred throughout the entire length of the genomes; CaHV1 was more distantly related to the other 3 viruses. Because of the similarities BEHV.N569 and BHV1. Cooper cloned DNA fragments were used to construct BamHI, BglII, BstEII, EcoRI, KpnI, and HindIII restriction site maps for the genome of BuHV1 and BamHI, BglII, and KpnI maps for the genome of BHV1.V155, a genital strain.