Brand community members have a strong interest in the product and in the brand. They usually have extensive product knowledge and engage in product-related discussions; they support each other in solving problems and generating new product ideas. Therefore, brand communities can be a valuable source of innovation. So far, little is known about the member's ability and willingness to participate in a company's innovation process. How does passion for the brand, affiliation to the brand community, and trust in the brand affect the willingness to engage in a company's innovation process? What is the effect of brand passion on brand knowledge and on domain-specific skills, which are considered important prerequisites for qualified and creative contributions to new product development? What is the effect of personality traits on the willingness and ability to engage in new product development? This research addresses these questions, which are interesting for managers who are thinking about opening up their innovation process and collaborating with brand communities and for academics exploring the opportunities of online communities for new product development and trying to develop promising new forms of open innovation networks. Drawing on brand community literature, relationship theory, creativity theory, and personality traits research, this paper introduces a comprehensive set of antecedents affecting brand community members' willingness to engage in new product development. It is argued that consumer creativity, identification with the brand community, and brand-specific emotions and attitudes (passion and trust) as well as brand knowledge are important determinants of consumers' willingness to share their knowledge with producers. The paper also identifies two personality traits (i.e., extraversion and openness) that have significant influence on brand passion, creativity, and identification with the community. The hypotheses are tested on a sample of 550 members of the Volkswagen Golf GTI car community. Structural equation modeling was used to test the relationship among the constructs. Though a positive disposition toward a brand may be advantageous for consumers that are willing to interact with producers during new product development, our results show that it is consumer interest in innovations and the innovative process that drives them to get involved. Further, brand community members with more knowledge and more innovative skills seem to be more willing to contribute than less qualified community members.