This study explores the application and effectiveness of Communication Accommodation Theory (CAT) in community service through a case study of the Happiness Makers Team at Deraya University. The study aims to understand how the Happiness Makers Team utilized CAT strategies in their communication with the community members they served and how these strategies affected their communication. The study used a qualitative case study approach, and the data were collected through semi-structured interviews with members of the team and community members they served. The analysis of the data reveals that the Happiness Makers Team effectively applied CAT strategies, such as adjusting their communication styles, using appropriate language, nonverbal behaviors, and tone of voice, to fit the communication needs of the community members. The application of CAT strategies led to improved communication and increased community engagement. The community members felt that the team members understood their communication needs and were willing to communicate with them, which facilitated the team's community service activities. The study concludes that CAT can be a useful framework for community service organizations to improve communication with the communities they serve. The study highlights the importance of adjusting communication styles to fit the communication needs of the interlocutors, which can lead to improved communication and increased community engagement. The study also suggests that CAT strategies can enhance the learning experience of students involved in community service activities by providing them with valuable communication skills that they can apply in their future careers