Little is known about how the knowledge of being a mutation carrier for Huntington's disease (HD) influences lives, emotionally and socially. In this qualitative study 10 interviews were conducted to explore the long term (>5 years) experiences of being a mutation carrier. The results showed a broad variety of both positive and negative impact on the carriers' lives. The most prominent positive changes reported were a greater appreciation of life and a tendency to bring the family closer together. On the other hand, some participants expressed decisional regrets and discussed the negative impact this knowledge had on their psychological well-being. The knowledge variously served as either a motivator or an obstacle in pursuing further education, career or investment in personal health. Deeper understanding of people's reactions to the certainty of knowing they will become affected with HD is essential for the genetic counseling team in order to provide appropriate support.