The objective of HARNESS is to train a multidisciplinary cohort of 13 PhD students in an international Doctoral Network, specialising in ethics, law, and technology. The network will offer comprehensive training, supervision, and secondments, allowing individuals to become experts in their specific disciplines while gaining practical knowledge across various fields. The program is supported by an excellent team of partners who are world leaders in their respective domains. The ethical and socio-technical impacts of the current and forthcoming AI and data-intensive information systems (e.g. Common European Data Spaces) require careful multidisciplinary consideration and foresight techniques regarding their alignment with EU's values, sovereignty and economic and societal goals. The new European regulations on data and AI should be supported by robust methods and tools to empower citizens and civil society to swiftly comprehend, navigate, and address emerging threats to fundamental rights. HARNESS will analyse the joint impact of new AI and data-intensive technologies and their regulation, considering legal entanglements, new legal compliance tools and the consequences that can be anticipated, from ethical, societal and economic perspectives. AI and data legislation will be formalised and operationalised under the 'Law as Code' paradigm using international standards and semantic web technologies. Specific cases such as AI Foundational models, impact of new regulations on competitiveness and the interplay of self-sovereign identity in Common European Data Spaces will be analysed in detail. HARNESS will utilise and build upon the state of the art in open information systems and knowledge engineering to develop appropriate methodologies, tools, and taxonomies to assist with regulatory compliance, deliberation and agreement on ethical norms. This will involve charting the constellation of possible systems, anticipating new risks and developing effective mitigations.