The numerous applications of femtosecond lasers during the last 15 years has necessitated a detailed understanding of pulse propagation coupled with ultrafast laser-material interactions. Current ultrashort pulse propagation models describe the evolution of fields with broad spectra while models of laser-induced ionization and laser-plasma interactions typically assume monochromatic laser fields. In this seminar I address the inherent contradiction of combining multi- chromatic propagation models with monochromatic laser-material descriptions. Recently published experimental and simulation results are presented that show how this contradiction leads to order-of- magnitude errors in calculating the ionization yield. Further simulation results suggest that multi-chromatic effects will alter the shape and severity of laser-induced modifications to the bulk of dielectric solids.