The human immunodeficiency virus type 1 (HIV-1) Rev protein is absolutely essential in the viral replication cycle, where it induces the production of viral structural proteins. Rev functions in part by inducing the nuclear export of incompletely spliced mRNA species specified by the presence of an RNA element, the Rev response element (RRE). Several proteins implicated in RNA processing and nucleo-cytoplasmic transport have been shown to interact with Rev, however, their exact roles remain unknown. To map potential protein recognition sites within the Rev structure, we have screened a phage library, displaying random 15-mer peptides, and isolated clones exhibiting similar sequences that specifically interact with Rev. The binding sites on Rev of the corresponding synthetic peptides were characterised by protein footprinting, involving partial proteolysis of radioactively end-labelled Rev protein. Two of the peptides produced a significant footprint within the nuclear export signal of Rev, raising the possibility that they mimic the binding of cellular protein factors implicated in nuclear export.