The service sector’s constant growth is followed by an increasing competition among service companies. Followed by this, the process of internal branding has become essential within the service brand building process, i.e. aligning the service company’s brand promise with employees’ behavior. Hence, customer- facing employees within the service organization have become a valuable and competitive asset as they manage to deliver the brand promise. A literature review showed that understanding the brand promise and brand commitment are two essential drivers of internal branding. An implicit and positive relationship between those two issues was presented. Absence of empirical studies regarding this relationship was revealed. The purpose of this thesis is to investigate the relationship between employees’ understanding of the brand and their brand commitment. The purpose motivated a hypothesis; employees understanding of the brand promise are positively associated with their brand commitment. The results are based on a quantitative survey conducted among customer- facing employees within the Swedish bank industry. The analysis is both founded in the discussion of the conceptual literature and the similar completed empirical study that was found within the research area. The findings of this research supported this thesis’ hypothesis. The relationship between bank customer- facing employees’ understanding of the brand promise and their brand commitment is shown to be positive and fairly strong. Almost two fifths of brand commitment can be explained by the understanding issue. However, it shows a need for further research in identifying more factors influencing employees’ commitment towards the brand.