Background: Despite the urgent need for palliative care for patients with advanced chronic obstructive pulmonary disease (COPD), it is not yet daily practice. Important factors influencing the provision of palliative care are adequate communication skills, knowing when to start palliative care and continuity of care. In the COMPASSION study, we address these factors by implementing an integrated palliative care approach for patients with COPD and their informal caregivers. Methods: An integrated palliative care intervention was developed based on existing guidelines, a literature review, and input from patient and professional organizations. To facilitate uptake of the intervention, a multifaceted implementation strategy was developed, comprising a toolbox, (communication) training, collaboration support, action planning and monitoring. Using a hybrid effectiveness-implementation type 2 design, this study aims to simultaneously evaluate the implementation process and effects on patient, informal caregiver and professional outcomes. In a cluster randomized controlled trial, eight hospital regions will be randomized to receive the integrated palliative care approach or to provide care as usual. Eligible patients are identified during hospitalization for an exacerbation using the Propal-COPD tool. The primary outcome is quality of life (FACIT-Pal) at 6 months. Secondary outcome measures include spiritual well-being, anxiety and depression, unplanned healthcare use, informal caregiver burden and healthcare professional's self-efficacy to provide palliative care. The implementation process will be investigated by a comprehensive mixed-methods evaluation assessing the following implementation constructs: context, reach, dose delivered, dose received, fidelity, implementation level, recruitment, maintenance and acceptability. Furthermore, determinants to implementation will be investigated using the Consolidated Framework for Implementation Research. Discussion: The COMPASSION study will broaden knowledge on the effectiveness and process of palliative care integration into COPD-care. Furthermore, it will improve our understanding of which strategies may optimize the implementation of integrated palliative care.