The purpose of this research paper is to examine select stock betas before and after September 11, 2001 in an attempt to identify a perceived change in market risk. To achieve this aforementioned purpose, definitions of historical betas, recent research using historical betas and finally research by the author will be analyzed. Thirty-five random stocks were selected from the January 28, 2005 issue of The Value Line Investment Survey and their beta data was then examined on an annual basis from September 1995 until September 2004. The historical beta data was then averaged and the standard deviation of each stock’s beta was computed. This was done to gain a better understanding of a “typical” beta movement. The research then examined in more detail the beta data that was recorded directly after September 11, 2001 (9-11). This was done to see the effects of 9-11, if any, on the movements of the 35 stocks selected. This movement was then compared to the overall movement of the New York Stock Exchange (NYSE) during the same time period. This analysis was done with the hope of determining if a clear market reaction to the 9-11 event could be identified. Through research, trends were seen in deviations over a period of ten years and the historical beta values directly following 9-11 were not more drastic than before. In fact the research appears to show that the beta values calmed down for a period of time.