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The excited-state dynamics of the vibrationless level of the $S2$ electronic state of each of two rotational conformers of guaiazulene were studied in a free jet. The technique used was saturated fluorescence spectroscopy; the data were fit using a three-state kinetic model. Both rotamers showed similar kinetics, dominated by a trapping rate of $1-2\times 109\sec -1$, which corresponds essentially to internal conversion. Absorption cross-sections of 1 {\AA}$\mathrm{<mrow\; data-mjx-texclass="ORD">2</mrow>}$ were obtained for these $0oo$ transitions. The applicability of various kinetic models and steady-state approximations under our experimental conditions has been examined.