Quasi-elastic neutron scattering measurements were performed on aqueous solutions of 3-picoline (3-methyl- pyridine) at room temperature. H-D substitution on both the solute and the water was used to separate the dynamics of the two species. The analysis of the translational diffusive mo- tion at different concentrations shows that at high picoline content the diffusion coefficient of water decreases strongly and becomes similar to that of the solute, indicating strong coupling between the motions of the solute and the solvent. Activation energies characteristic of the dynamic behavior of the methyl group were determined from 1 H spin-lattice re- laxation rate measurements for H2 Oa nd D 2O solutions of 3-picoline above 310 K.