To develop a psychometrically sound tool for measuring the knowledge of nursing and care staff about the experience, assessment and management of pain in older people (including people with dementia) for use in the residential aged care setting.The Pain in Older Adults Knowledge Survey (POAKS) was developed and tested in two phases. Phase 1 involved developing an initial item pool with good content validity based on a review of the research literature and a modified Delphi technique involving national and international experts. A pool of 24 items was developed for testing. Initial testing of the psychometric properties of the POAKS with 30 university employees led to refinement and final wording of items. Phase 2 involved testing of the psychometric properties of the POAKS with 279 respondents, including first year (n = 176) and third year (n = 70) nursing students and staff in a residential aged care service (n = 33).Results established the content validity and internal consistency of the POAKS and supported its use as an instrument to measure nursing staff knowledge about the experience, assessment and management of pain in older people.The POAKS will enable residential aged care facilities to measure the level of knowledge among nursing and care staff about pain in older people (including people with dementia). The measure provides a basis for the development and implementation of educational interventions to address knowledge gaps that may impact on the quality of care provided.