BACKGROUND:Organizational culture in group homes for people with intellectual disabilities has been identified as influencing staff behaviour and residents' quality of life (QOL). Despite this influence, culture has been under-researched, with no published and validated instrument to measure its dimensions in group homes. The aim was to develop such a measure. METHOD:The Group Home Culture Scale (GHCS) was developed using a theory-driven approach. Items were generated from the research literature, which were reviewed by experts and tested in cognitive interviews. Data from 343 front-line staff were used for exploratory factor analysis. RESULTS:The content and face validity of the GHCS were found to be acceptable. Exploratory factor analysis indicated that the GHCS measured seven dimensions of group home culture. Cronbach's alpha for the dimensions ranged from 0.81 to 0.92. CONCLUSIONS:The GHCS has potential use in research to determine whether dimensions of group home culture predict the quality of staff support and residents' QOL.