This thesis examines how communication technology is used for creating a democratic and committed participation within collective action organizations (CAOs). This is achieved by illuminating how organizations' structure and culture relate to their communication. It’s done by in-depth interviews with network-based movements and association-based organizations, and analyses of their digital newsletters. The analysis is based on affordance-driven theory, capturing the interaction between organizations and their digital platforms. The focus lies on how internal democracy and collective action are afforded or constrained to some degrees. Degrees of deliberation for creating common ground and active participation are made visible by using the concept of communicative action. Theories within social movement studies, such as collective action, broaden the understanding of how the perception of digital tools shapes and is shaped by their structure and culture. The results show that the usage and coordination of communication channels is essential for the practice of internal democracy in everyday work, beyond annual meetings and board meetings. Independent chat-based platforms enable an increased control of conversations, cooperation and coordination, while information overload and effective decision- making processes can hinder democratic participation. Commercial social media platforms such as Facebook enables new flows of engagement and connectivity but constrains coordination and control of the framing process within Facebook groups. Additionally, unpredictable algorithms and advertising policy on Facebook makes it difficult to reach out. Overall, the study suggests a broadened view of communication, where communication and usage of digital media should not be considered as instrumental entities. Rather, it is strongly related to how channels are being coordinated, how organizations are organized and the view of participation. Formal structures can both hinder and enable increased communicative action that contributes to democratic participation.