sentences:  The Court's holding means that liability for an individual defendant sued under §1983, who can be liable for any constitutional violation (absent immunities), even if the conduct is unauthorized or a one-off incident, is very different from liability for municipal entities, who can be sued under §1983 only pursuant to a policy or custom.This can mean either an affirmative policy or custom or a policy by omission.In subsequent cases, the Court defined what constituted a policy or custom for purposes of "Monell" liability.