It is an indisputable fact that Corporate Social Responsibility (CSR) has emerged in recent years, as both an important academic construct and a pressing corporate agenda item. A number of researchers have emphasized the crucial role of CSR initiatives in providing the companies with a series of benefits. From a marketing perspective, some of the benefits for socially responsible companies are higher purchase intentions and advocacy behavior, like positive Word of Mouth. Considering the growth of CSR initiatives by companies it becomes important to understand better the consumers’ reactions to them. This paper seeks to examine the relative importance that consumers attach to CSR and CSR initiatives and their impact on consumer behavior in the Greek mobile telecommunication industry. The results indicate that Greek consumers consider the CSR very important, rank the CSR initiatives which focus on the environmental protection highly, are willing to change service provider for a more social responsible one and last but not least, they are more sensitive to negative CSR publicity than the positive one.