Excimer laser photolysis in combination with time-resolved IR laser absorption detection of OH radicals has been used to study O-3/OH(v = 0)/HO2 chain reaction kinetics at 298 K, (i.e., OH + O-3 -->(k1) HO2 + O-2 and HO2 + O-3 -->(k2) OH + 2O(2)). From time-resolved detection of OH radicals with high-resolution near IR laser absorption methods, the chain induction kinetics have been measured at up to an order of magnitude higher ozone concentrations ([O-3] less than or equal to 10(17) molecules/cm(3)) than accessible in previous studies. This greater dynamic range permits the full evolution of the chain induction, propagation, and termination process to be temporally isolated and measured in real time. An exact solution for time-dependent OH evolution under pseudo-first-order chain reaction conditions is presented, which correctly predicts new kinetic signatures not included in previous OH + O-3 kinetic analyses. Specifically, the solutions predict an initial exponential loss (chain "induction") of the OH radical to a steady-state level ([OH](ss)), with this fast initial decay determined by the slim of both chain rate constants, k(ind) = k(1) + k(2). By monitoring the chain induction feature, this sum of the rate constants is determined to be k(ind) = 8.4(8) x 10(-14) cm(3) molecule(-1) s(-1) for room temperature reagents. This is significantly higher than the values currently recommended for use in atmospheric models, but in excellent agreement with previous results from Ravishankara et al. [J. Chem. Phys. 1979, 70, 984].