This volume offers comprehensive reviews on the mechanism of cap-independent translation of viral and cellular mRNA molecules. The chapters include recent findings on cap-independent translation by internal ribosome binding of picornaviral, hepatitis C viral and certain cellular mRNAs and disuss the mechanisms underlying cap-independent translation of adenoviral and heat shock mRNAs. Using new technologies in the field, new features of the eukaryotic translational apparatus have been uncovered and their roles in translational initiation and its regulation are probed.