Corporate social responsibility (CSR) is becoming increasingly more important for firms in today' s global marketplace. Thus effective communication of a company's CSR initiatives is vital toward enhancing a company's reputation and in tum, its sales revenues. With this consideration, the corporate reputations of firms in the Aerospace and Defense (A & D) industry worldwide, in conjunction with their use of social media were examined. An objective of the research was to validate a link between the use of social media to communicate CSR activities and a firm's reputation ranking. Methodology for the study involved the use of a qualitative content analysis of the online and social media presence of the top 20 A & D companies from the Deloitte Toche Tohmatso Limited (DTTL) 2014 Global A & D sector financial performance study. Data from six indicators of CSR: environment, community relations, diversity, employee relations, human rights, and client comments was obtained and examined. According to the findings, firms utilizing social media as a communication channel should expect improved reputation ratings. All top 20 A & D companies publish at least four CSR indicators on their social media platforms. Results indicate that reputation rating rose when five CSR indicators were reported, however, the addition of a sixth indicator did not increase a firm's rating. The conclusion reached is that while CSR content via social media can lead to higher reputation ratings, companies do need to carefully choose the ideal number of CSR indicators, as well as which indicators, to position themselves. Development of a social media strategy to communicate CSR activities would thus benefit firms.