Coherent anti-Stokes Raman scattering (CARS) spectroscopy of gas-phase CO 2 is demonstrated using a single femtosecond (fs) laser beam. A shaped ultrashort laser pulse with a transform-limited temporal width of ∼7 fs and spectral bandwidth of ∼225 nm (∼3500 cm −1 ) is employed for simultaneous excitation of the CO 2 Fermi dyads at ∼1285 and ∼1388 cm −1 . CARS signal intensities for the two Raman transitions and their ratio as a function of pressure are presented. The signal-to-noise ratio of the single beam-generated CO 2 CARS signal is sufficient to perform concentration measurements at a rate of 1 kHz. The implications of these experiments for measuring CO 2 concentrations and rapid pressure fluctuations in hypersonic and detonation-based chemically reacting flows are also discussed.