Quantitative analysis of laser-induced fluorescence signals of nitric oxide requires properly accounting for the effects of temperature, collisions, and laser and detection properties on the meas-ured signals. Over the past years, LIF properties of nitric oxide were studied for a range of condi-tions, from well-controlled burners to internal combustion engines. The knowledge gained from these studies has been compiled into a model and software tool that now allows the computation of LIF spectra/signals for given experimental conditions. However, the excitation dynamics are treated in a simplified fashion. Here we discuss the role of non-stationary excitation dynamics on the LIF signal utilizing a comprehensive, time dependent, multi-level rate equation model.