In a nursing home case study using observation and interview data, the authors described two mental models that guided certified nurse assistants (CNAs) in resident care. The Golden Rule guided CNAs to respond to residents as they would want someone to do for them. Mother wit guided CNAs to treat residents as they would treat their own children. These mental models engendered self-control and affection but also led to actions such as infantilization and misinterpretations about potentially undiagnosed conditions such as depression or pain. Furthermore, the authors found that CNAs were isolated from clinicians; little resident information was exchanged. They suggest ways to alter CNA mental models to give them a better basis for action and strategies for connecting CNAs and clinical professionals to improve information flow about residents. Study results highlight a critical need for registered nurses (RNs) to be involved in frontline care.