A conceptual model and objective scale for measuring resistiveness to care in individuals with advanced dementia of the Alzheimer type (DAT) were empirically generated from the perspective of nursing staff caregivers and through observation of residents with DAT. The resistiveness to care scale (RTC-DAT) was judged to have content validity and reduced to 13 items. Quantifiable scoring procedures and methods for rating videotapes and conducting clinical observations were developed. The RTC-DAT was tested with 68 subjects at three sites. The RTC has a range of 0-156. Initial testing provided reliability estimates of .82-.87 for internal consistency and good to excellent kappas. Criterion-related validity with observed discomfort and construct validity by factor analysis support the RTC-DAT. Measurement issues and recommendations for use in research are discussed.