The overall aim of this thesis is to investigate the effects of coherence in the corporate branding process. Specifically, this thesis defines and develops the concept of corporate brand coherency (CBC) using four antecedents and four dimensions, and investigates the effects of incongruence based on the advertising antecedent by manipulating ad-brand congruence. Using the Elaboration Likelihood Model (ELM), the research tests whether two-sided messages aid the resolution of incongruence following central route processing and whether greater number of arguments could act as a peripheral cue. Accordingly, a conceptual model was developed to test the effects of ad-brand congruence, message sidedness and argument quantity on corporate credibility, attention and elaboration, attitude towards the ad and attitude towards the corporate brand. To empirically test this model an online experiment (using a 3x2x2 between-subjects factorial design) was conducted, where subjects were exposed to a modified print advertisement for a grocery store. A total of 528 responses were collected from New Zealand Internet users. Two- and three-way ANCOVAs as well as path analysis was used to analyse the hypothesised relationships. The results indicate support for CBC, as it was found that congruence led to positive evaluations and higher corporate credibility. Two-sided messages were not found to be effective in reducing the negative effect of incongruence. Instead, two-sided messages led to less favourable evaluations of incongruence. Regardless of the incongruence, the results show that two-sided messages did not lead to positive evaluations, while an increased number of arguments did lead to more favourable attitudes. Overall, the findings show the ELM is not applicable to explain consumers’ responses to incongruence, as incongruence was not found to affect message processing. Additionally, there was no support that message sidedness and argument quantity, respectively, acted as central and peripheral cues. Furthermore, findings indicate that incongruity in advertising can lead to positive evaluations when consumers have a negative prior brand attitude. The theoretical and managerial implications as well as directions for future research based on these findings are discussed.