Mechanical properties and structure were studied for undrawn and zone-drawn films of LARC-CPI thermoplastic polyimide. The dynamic modulus of undrawn glassy material ranged from about 1.8 to 4.3 GPa, depending upon the degree of crystallinity. After zone drawing to draw ratios of 3.6-4.0, the dynamic glassy modulus was increased to a maximum of 9.5 GPa. The highest moduli were attained in samples that were multiply zone-drawn. The maximum-achievable draw ratio increased with the maximum drawing temperature, but the semicrystalline nature of the starting material limited the ultimate drawability. For the first time, highly oriented crystalline films were obtained for X-ray diffraction and preliminary crystal structure analysis. The crystal lattice was fit to the orthorhombic crystal system, and the results indicate that the lattice parameters are a = 8.0 +/- 0.2 angstrom, b = 5.9 +/- 0.2 angstrom, and c = 36.5 +/- 0.3 angstrom. The value of the c-axis lattice parameter is very close to the fully extended chain length of the monomer repeat unit.