Previous studies on the antecedents of Electronic Word of Mouth (EWOM) have either focused on the opinion leadership characteristics of individuals, or on brand commitment. It is the aim of this study to combine these two separate streams of research by evaluating the impact of opinion leadership characteristics and brand commitment as possible drivers of EWOM on Social Networking Sites (SNS). It is found that brand commitment is indeed a strong driver of brand related EWOM. Brand commitment mediates the motivation to engage in EWOM by ...