Tertiary amine dendrimers with both hydrophilic and hydrophobic chains on every end were synthesized from poly(propyleneimine) dendrimers DAB-dendr-(NH2)(n) (n = 8, 32, and 64) using sequential amidations and LiAlH4 reductions. The tertiary amine dendrimers were quaternized completely with methyl iodide and converted to quaternary ammonium chlorides by ion exchange. The quaternary ammonium chloride dendrimers are soluble in both organic solvents and water. C-13 NMR spin-lattice relaxation time (T-1) measurements show that the conformations of the dendrimers depend on solvent. The quaternary ammonium chloride dendrimers solubilize lipophilic compounds, such as pyrene and Reichardt＇s dye, in aqueous solution. The limiting solubility corresponds to one pyrene per dendrimer molecule. The rates of the decarboxylation of 6-nitrobenzisoxazole-3-carboxylic acid in aqueous solutions of the cationic dendrimers were up to 500 times faster than in water alone.