Export of mRNA through nuclear pore complexes (NPC) is preceded by multiple and well coordinated processing steps, resulting in the formation of an export competent ribonucleoprotein complex (mRNP). Numerous factors involved in the translocation of the mRNP through the NPC and its release into the cytoplasm have been isolated mainly through genetic approaches in yeast, and putative functional homologues have been identified in metazoan systems. Understanding the mechanism of mRNA export relies, in part, on the functional characterization of these factors and the establishment of a complete network of molecular interactions. Here we summarize recent progress in the characterization of yeast and mammalian components implicated in the export of an mRNA from the nucleus to the cytoplasm.