Evaluation of efforts to support family caregivers of people with dementia in their daily medical management responsibilities requires a measure of caregiver self-efficacy (confidence). This article describes the development and psychometric properties of the Caregiver Confidence in Sign/Symptom Management (CCSM) scale, the only available instrument in this area. Measurement development included literature and expert panel review, cognitive testing, and field testing. The CCSM is a 25-item measure (α = .92) composed of confidence in relation to 4 subscales: knowledge of signs/symptoms (α = .83), management of cognitive signs/symptoms (α = .85), management of medical signs/symptoms (α = .87), and general medication management/responsiveness (α = .85), all of which relate to caregiver role strain. The CCSM is a reliable and valid instrument to assess caregiver confidence in sign/symptom management and is useful to determine caregiver needs and outcomes of related interventions. Additionally, it furthers understanding of the role of self-efficacy in caregiver quality of life.