Author Institution: Guelph-Waterloo Centre for Graduate Work in Chemistry, University of WaterlooA study of collisional line broadening calculations using a variety of theoretical methods on an atom-diatom system has been performed. The full close coupled quantai calculation is compared with the centrifugal sudden approximation (CSA), the ``corrected'' centrifugal sudden approximation (CCSA), the infinite order sudden approximation (IOSA) and a semiclassical trajectory method for the HF-He interaction. The accuracy and relative cost of each method will be discussed