The interpreter sits in an interpreting booth, listens to the speaker through a headset and interprets into a microphone while listening. Delegates in the conference room listen to the target-language version through a headset.
Theoretical issues: An important question is whether simultaneous interpreters actually translated simultaneously, that is whether they actually listened and spoke at the same time. The next important question pertaines to the nature of the mental activities which take place during simultaneous interpreting. Much has still to be learned about speech perception and production as part of the process which are assumed to take place. However and for instances, as regards to production, it is stressed that because of the risk of loss involve when lagging too far behind the speaker, interpreter often have to start formulating their TL (Target Language), sentences before having a full picture of the idea to be expressed. Speech comprehension by the interpreter’s knowledge of the subject is another aspect which will be inferior to that of the participants and it will impact negatively. Simultaneous interpreting is very intense work, therefore, it often requires at least two interpreters to take turns. Each one typically interprets for about 20 to 30 minutes and takes a 10-minute break in between meetings. It is important that the interpreter remains alert or the interpretation might suffer. Simultaneous interpreting is also done by signed language interpreters (or interpreters for the deaf) from a spoken into a signed language and vice versa. Signed language interpreters do not sit in the booth; they stand in the conference room where they can see the speaker and be seen by the other participants.