In the coming decade, a seamless integration of our on- and offline lives will be necessary for a sustainable digital society. This requires urgent multi-disciplinary debate on the collection, control and use of personal data in society. This paper proposes a framework that can be used to shape this dialogue. It is based on a neutral and consistent terminology that may support a constructive and fruitful debate, avoiding terms that have too often led to controversy and confusion. We have attempted to position in this structure state-of-the-art technology developments, including context-awareness, user-centred data management, trust networks and personal data ecosystems. It demonstrates clear relations between ongoing work in various groups and hence an urgent need for cooperation to achieve common goals. We argue that such cooperation can lead to the emergence of a personal data ecosystem that may truly support a sustainable digital society.