Many older people living with dementia experience multimorbidity, which has been described as the presence of two or more long-term conditions, such as congestive heart failure, type 2 diabetes or stroke. Each of these long-term conditions can cause a wide range of symptoms and almost all can involve pain. Older people may also experience sensory impairments, such as hearing and vision loss, which in those with dementia can lead to symptoms similar to the behavioural and psychological symptoms of dementia. In addition, older people with dementia can experience challenges with expressive and receptive communication. All these factors can make it challenging for nurses to effectively identify and manage symptoms related to long-term conditions in older people with dementia. This article provides an overview of multimorbidity in older people with dementia, using pain as an example of a symptom associated with multiple long-term conditions to illustrate the complexities of symptom recognition and management in this population. The authors also consider how communication issues, sensory impairment and diagnostic overshadowing can add to the complexities of symptom recognition and management, and outline some of the implications for nursing practice.