In situations where you can count on participants of more than one nationality, an interpreter is required for each language. For example: a lecture where the speaker is American and the audience has Brazilian and Argentine listeners, 2 interpreters will be needed: a translator from English to Portuguese and other to translate from English to Spanish.

First, for your event to take place in the best way, you need an environment with good visual and auditory quality. It will also be necessary to have a booth with acoustic insulation and devices such as microphones, headphones, a sound table, receptionists to deliver equipment to participants, as well as a technician for installation and support during the event. 

With all this prepared, the language translator will stay inside a booth with acoustic insulation and headphones, listening carefully to what the lecturer or speaker says and, simultaneously, passing on the translation of what the speaker says to the public, who will listen to the translation through headphones.