The General Data Protection Regulation (GDPR) mandates that organisations keep a Record of Processing Activities (RoPA) and ensure compliance. The RoPA should include details on processing personal data from internal departments with diverse IT systems and external data processors. Current practices rely on spreadsheets or proprietary systems, which lack machine readability and interoperability, creating obstacles to automation. Regulators report that organisations face challenges in maintaining an accurate and up-to-date RoPA. This thesis defines an approach to supporting ‘Electronic Records of Processing Activities’ (ERoPA) to help organisations comply with the GDPR Accountability Principle. The “ERoPA Approach” facilitates the collection, representation, transfer, and review of information to support organisational GDPR compliance through the automation of RoPA processes based on stakeholder requirements. Using the Action Design Research (ADR) methodology, fourteen stakeholder requirements for the ERoPA Approach were identified. The ERoPA Approach was developed iteratively through ADR to provide: (i) an ontology to support the representation of RoPAs based on a survey of RoPA templates published by GDPR regulators, (ii) an interoperable machine-readable approach for the collection and transfer of RoPA information, and (iii) queries to support typical compliance tasks and (iv) deployment guidelines for practical implementations based on a case study in a real organisation where observations were gathered, and the opinions of data protection experts were consulted. The main contribution of this thesis is the ERoPA Approach, which enhances GDPR accountability by facilitating the collection, representation, transfer, and review of RoPA information exchanged among stakeholders in data processing chains. The ERoPA Approach enables sharing GDPR accountability information with regulators and certification bodies, significantly improving the visibility and efficiency of organisational accountability practices. Additionally, it provides tools to support GDPR compliance automation. A minor contribution of this research is the extension of the W3C Community Standard, Data Privacy Vocabulary (DPV), to represent RoPAs.