The quality of care in nursing homes has generally improved since the implementation of the OBRA-1987; however reports of serious problems such as inadequate pain management, pressure sores, malnutrition, and urinary incontinence persist. While the primary concern remains lack of staffing, investigators have found that even the highest staffed nursing homes are deficient in some care processes. It has been suggested that a lack of effective management structure may be a contributing factor. There is theoretical and empirical evidence to suggest that effective management structure is best guided by the complexity of work performed by the organization. The purpose of this study was to develop a reliable and valid instrument to measure nursing care complexity in nursing homes. Items were developed based on a comprehensive review of the literature and the adaptation of items from existing instruments to make them relevant to the nursing home setting. Content validity was evaluated by nurse experts with extensive knowledge of the theory and/or nursing home care. One hundred sixty-eight direct care providers from seven nursing homes located in central and southern Arizona participated in the study.Reliability was estimated using Cronbach's alpha. Reliabilities using individual level data were generally acceptable for a new scale, however, the alpha for the client technology subscale was low (total scale = .78, client technology = .65, operations technology = .78, and knowledge technology = .79). Exploratory factor analysis demonstrated three domains of nursing care complexity as conceptualized. Explained variance for the 3 factors was 36.19%. There was a very modest correlation of the instrument with an established instrument of work unit technology and a modified magnitude estimate of nursing care complexity. One subscale (knowledge technology) discriminated between nursing subunits in the nursing home.The instrument demonstrated modest psychometric properties in measuring nursing care complexity in nursing homes. The strength of the instrument is its ability to measure domains of work complexity based on theory from organizational and nursing science. Further investigation is needed to strengthen the psychometric properties of the instrument and to determine its usefulness in measuring nursing care complexity in nursing homes.