We present new experimental atomic transition values for the atomic emission spectrum of doubly ionized argon, Ar III. In this work we studied 3s23p4 — 3s23p33d, 3s23p4 — 3s23p34s , 3s23p4 — 3s23p34d, 3s23p4 — 3s23p35s, 3s23p33d — 3s23p34p, and 3s23p34s — 3s23p34p transition arrays and 196 lines were identified as new atomic transitions between levels of these configurations. The experimental data were obtained from a capillary-discharge tube. The identifications are supported by multiconfiguration Hartree-Fock relativistic calculations.Centro de Investigaciones ÓpticasFacultad de Ciencias Astronómicas y Geofísica