Firms have adopted corporate social responsibility(CSR) as one of important managerial and strategic considerations with the increasing pressure and expectation of society in which they operate. A number of scholarly work on CSR has been conducted mainly by identifying its elements and validating the effects of CSR on firm performance. However, several important aspects have received relatively little attention. First, to date, little academic research has explored an aspect of corporate irresponsibility, particularly in Korea. The last decade have witnessed that firms can be simultaneously responsible and irresponsible. Second, most previous studies examining the relationship between CSR and firm value have provided mixed results. Moreover, CSR effects vary depending on the explored each specific element of CSR. Third, most previous studies conducted in Korea have utilized the KEJI index as a proxy of CSR performance. However, little attention have addressed the validity of KEJI as a proxy of CSR performance. Given this gap, this paper explores two questions. Does CSR performance lead to higher firm value? And, does CSR performance reduce corporate social irresponsibility(CSiR)? First, this study suggested a comprehensive framework to better understand CSR by simultaneously considering CSiR and firm value. Second, this study provoked discussion on the validity of CSR measurement. Third, this paper provided empirical evidence of the effects of CSR on CSiR and firm value. Consistent with the purpose of this study, the study utilized three proxy measures for CSR, CSiR, and firm value. First, a six-year panel of the KEJI index from year 2005 through year 2011 (except 2008) was used for CSR performance. Second, the study collected data regarding corporate irresponsibility activities by searching daily newspaper articles and Fair Trade Commission's database of resolution for prosecution with 48 keywords representing corporate scandals from 2005 through 2012. Third, this study used Tobin's Q for measuring firm value. Hierarchical regression analyses with time-lag models were used to test the effects of CSR on CSiR and firm value, respectively. Overall, the research results provide mixed results regarding the effects of CSR. First, CSR, measured by the KEJI index, has positive and significant impact on firm value. The effects of CSR differ depending on specific dimensions of CSR. However, overall CSR performance is found to contribute to higher firm value. This result well illustrates that the CSR effect is consistent with the previous studies so that the financial aspect of predictive validity of the CSR measure, the KEJI index, is significant. Second, the result confirms that there is no signifiant positive or negative relationship between CSR and CSiR. This result indicates that the commonly used measure for CSR performance in Korea might have shortcomings in terms of validity to predict the possibilities of corporate irresponsible incidents in near future. Collectively, the results of this study reveals that the effect of CSR performance and predictive validity of the KEJI index on firm value are significant whereas they are not significant on corporate irresponsibility. Through a comprehensive model and empirical evidence, this study provides a better understanding of CSR and its measurement. This study provokes an open discussion about CSR by suggesting a controversial result to the conventional expectation on the effects of CSR.