Customer involvement in innovation activities is a common practice among companies in most industries. It has been widely researched by scholars to demonstrate its risks and advantages. Yet, the growing importance and recognition of the Internet are transforming the scope, boundaries, and dynamics of interactions among firms and customers. Progressing information and communication technologies (ICTs) (including the Internet) enable faster, cheaper, and more efficient collaboration. The demonstrated benefits of using various web-based methods for customer involvement in innovation activities have encouraged companies to adopt a new approach. Despite this, there is a lack of knowledge about associated challenges. In addition, prior research was unable to provide empirical evidence of the claimed benefits ensuing from web-enabled customer involvement. As a result, companies may experience unforeseen difficulties and may not be able to achieve what they expect from their implementation of web-based methods. This thesis aims to address this research gap by exploring web-enabled customer involvement from a firm’s perspective. The overall purpose of this dissertation is to increase the understanding of web-enabled customer involvement in innovation activities by exploring its use and its impact on firms’ innovation, as well as management competences needed for its efficient realization. The thesis draws on the concept of absorptive capacity and includes four empirical studies from various industries. The adoption levels of a wide range of web-based methods were identified and compared with the findings of the previous study, thereby uncovering interesting changes in their popularity, as well as differences in adoption among companies in various industries. The empirical findings of this thesis show that web-based methods increase a company’s probability to introduce service innovations. Three types of challenges related to different types of web-based methods were identified and verified. It was also possible to identify corresponding management practices to handle these challenges. The management practices form three firm competences, constituting a specific absorptive capacity. It was proved that all dimensions of this specific absorptive capacity are needed for successful and effective customer involvement. Insights of this thesis contribute to increasing the understanding of web-enabled customer involvement. Therefore, the thesis provides companies with empirically verified knowledge that is necessary to make decisions about the implementation and management of web-enabled customer involvement.