Context Delirium occurs commonly in settings of palliative care (PC), in which patient vulnerability in the unique context of end-of-life care and delirium-associated impairment of decision-making capacity may together present many ethical challenges. Objectives Based on deliberations at the Studies to Understand Delirium in Palliative Care Settings (SUNDIPS) meeting and an associated literature review, this article discusses ethical issues central to the conduct of research on delirious PC patients. Methods Together with an analysis of the ethical deliberations at the SUNDIPS meeting, we conducted a narrative literature review by key words searching of relevant databases and a subsequent hand search of initially identified articles. We also reviewed statements of relevance to delirium research in major national and international ethics guidelines. Results Key issues identified include the inclusion of PC patients in delirium research, capacity determination, and the mandate to respect patient autonomy and ensure maintenance of patient dignity. Proposed solutions include designing informed consent statements that are clear, concise, and free of complex phraseology; use of concise, yet accurate, capacity assessment instruments with a minimally burdensome schedule; and use of PC friendly consent models, such as facilitated, deferred, experienced, advance, and proxy models. Conclusion Delirium research in PC patients must meet the common standards for such research in any setting. Certain features unique to PC establish a need for extra diligence in meeting these standards and the employment of assessments, consent procedures, and patient-family interactions that are clearly grounded on the tenets of PC. �� 2014 American Academy of Hospice and Palliative Medicine. Published by Elsevier Inc. All rights reserved.