Despite the unquestionable relevance of ensuring effective oral care for patients with advanced cancer, inadequate research activity has been directed towards developing and evaluating specific mouth care regimes for this group of seriously ill patients. The prevalence of the problems experienced by these individuals is well known and ensures that we have a clear picture of the areas where practice development is urgently needed. This paper presents a critique of research-based oral care interventions through a consideration of the management of the following problems: coated mouth and tongue; dry mouth; infection (fungal, viral, bacterial); pain; altered taste. Where possible, research findings are presented, but for many of the areas of care it is possible only to offer guidelines based upon an understanding of the normal structure and function of the oral cavity, the agents and tools currently in use, and practice-based evidence. There is an urgent need for a coordinated body of research activity within this field.