The era of data sovereignty has arrived and the world is transforming into a data-driven society. This book begins its discussion with ownership of data from a big data and personal data perspective. Innovative services that combine technologies such as blockchain, VR/XR, and AI are being released every day, but it is personal data that eventually leads to innovative services. Accordingly, ownership, scope and method of use of data are changing. It is changing from centralized to decentralized, from corporate ownership to personal ownership, and from big data-based to personal data-based use. In terms of data sovereignty and GDPR, MyData and the expected changes it will brings are described, and the impact of AI on MyData is dealt with in depth. The author presents an approach for human-centric & practical MyData implementation, and specifically proposes a technical approach for the utilization of personal data based on data sovereignty. In addition to policy discussions on data sovereignty and issues surrounding personal data, the studies on the application of data technology are summarized at a glance. It is a book that can enhance the understanding of changes in MyData technology, policies, and markets.