Aim To explore the perceptions of staff caregivers regarding factors affecting optimal nutrition and hydration for individuals living in Specialised Dementia Care Units in New Zealand. Methods Qualitative descriptive study using a semi‐structured interview approach with 11 staff caregivers at two Specialised Dementia Care Units. Data were analysed using a general inductive approach. Results Two main themes were identified. The first theme ‘It's about the individual’ encompassed individual factors such as appetite, food appeal, and cognitive and functional abilities. The second theme ‘It's about the environment’ encompassed factors relating to the dining environment, the social aspects to dining and the provision of support with mealtime activities. Conclusions Factors affecting nutrition and hydration in people living with dementia are complex and inter‐related. Organisations providing specialised dementia care, their staff and foodservice providers should focus on both the individual and environment to ensure optimal nutrition and hydration for the people in their care.