The EPR spectrum of isolated Cu+2 ions in NaCl obeys an axial spin Hamiltonian at low temperatures with g∥=2. 373, g⊥=2. 07, A∥=95 G, A⊥=40 G, Q'=20 G with the z axis lying parallel to one of the cube edges. Upon warming toward room temperature, the ligand huperfine spectrum disappears as the linewidth increases from 16 G at 4.2 K to 25 G at 77 K. At 95-100 K, as this spectrum disappears, a single isotropic line appears with g=2.16 and a linewidth of 60 G. These low- and high-temperature spectra are interpreted as the static and dynamic Jahn-Teller distortions of the CuCl complex. A static strain experiment performed at 77 K results in a repopulation of the three distortion sites and enables a measurement of the strain coefficient V2 to be made.