Abstract: This invention relates to an external defibrillator whose language of operation can be easily changed when the defibrillator is deployed for use. Defibrillators include, manual defibrillators, automatic or semi-automatic external defibrillators ("AEDs") and defibrillator trainers. In one embodiment, the invention provides a way to change the language in which the defibrillator delivers instructions to a user. Defibrillators of this invention would contain multiple languages in their memory. During the set-up of the defibrillator some or all of the languages could be designated as a language in which a prompt will be offered. Additionally, during set-up, one language will be designated as the default language. Once the defibrillator is deployed for use in an emergency, the operator will indicate a language preference for the defibrillator operating instructions.