“Standard of care” sounds like a medical term, but actually it is a universal legal concept. It is codified differently by individual state statutes and is written into each state's uniform jury instructions. The phrase increasingly appears in scientific articles discussing the management of patients with headache. But, the term usually is not defined nor is evidence presented to justify the notion that the so-called standard has any scientific basis. In a courtroom, jury instructions using this phrase can be a legal sword aimed at a defendant doctor, rather than a shield. At risk is a physician's basic right to care for a patient according to that individual's particular needs.