To study the reorientational motion of BH 4 groups and the translational diffusion of Li + ions in the novel bimetallic borohydride chloride LiLa(BH 4 ) 3 Cl, we have measured the 1 H, 11 B, and 7 Li NMR spectra and spin−lattice relaxation rates in this compound over the temperature range of 23−418 K. At low temperatures (T < 110 K), the proton spin− lattice relaxation rates are governed by fast reorientations of BH 4 groups. This reorientational process can be satisfactorily described in terms of a two-peak distribution of the activation energies with the peak E a values of 41 and 50 meV. Above 200 K, the NMR data are governed by a combined effect of two types of motion occurring at the same frequency scale: Li ion diffusion and another (slower) reorientational motion of BH 4 groups. These results suggest that the Li ion jumps and the slower reorientational jumps of BH 4 groups in LiLa(BH 4 ) 3 Cl may be correlated. The estimate of the tracer Li ion diffusion coefficient at room temperature (5.2 × 10 −8 cm 2 /s) following from our experimental data indicates that LiLa(BH 4 ) 3 Cl can be considered as a promising solid-state ionic conductor.