At the March 26–30 meeting of the American Chemical Society in San Francisco, a new type of peptide tag was described that can smuggle water-soluble drugs, such as Taxol (paclitaxel) and cyclosporine, through the cell membrane. This peptide tag comprises a repeating series of up to nine arginine residues that resembles the cationic subunits of HIV Tat protein, a natural viral protein that also boosts the uptake of drugs into target cells (Nat. Biotechnol. 17, 942, 1999). Using different cationic amino acids and ornithine (a structural analog of arginine), Paul Wender and his team have shown that the remarkable properties of the arginine tag are attainable to it's hydrogen bonding capacity. In a related study in J. Am. Chem. Soc. (122, 2671–2672, 2000), Steven Regen and colleagues have designed molecular umbrellas, comprising an inner hydrophilic layer and an outer hydrophobic lipid layer, that can be used to envelop a drug, protect it within the membrane, and release it into the cytosol. The system is now being tested with genuine peptide and nucleic acid drugs.