Diversity characteristics such as culture, sexual orientation, and social situation potentially impact the participation of older individuals in healthcare. An awareness of diversity characteristics and their potential to impact on older people's access to health and aged care by professionals through training is important. This paper outlines the development and initial validation of a survey using adapted Delphi methodology and distribution to 195 health and aged care professionals pre- and post-diversity training. An initial pool of 31 items were developed with an expert reference group and reduced to 21 through exploratory factor analysis. A two-factor solution was extracted, measuring skills and attitudes of professionals relative to providing services to older people with diverse characteristics. Internal consistency of the items yielded a Cronbach alpha of 0.78. T-tests conducted on the pre- and post-survey data showed significantly higher scores on the domains of skills and attitudes following the training. Knowledge was not effectively captured using this method, with true-false or free-recall questions being a more appropriate approach. This tool fills a gap in the evaluation literature, providing an important first step to assess outcomes of diversity training in community aged care. Further validation is necessary for the tool to be used more widely in the sector.