Simultaneously means that the interpreters have no time to think and find the best formulations, so they not only have to be prepared on the topic, but also have enough experience and know how to solve problems, how to abbreviate without losing elements from the source speech and reformulate sentences according to the grammatical rules in the target language (e.g. put the verb at the end when interpreting into German language or solve the lack of the verb while interpreting from German language).

Depending on the type of simultaneous interpretation, different equipment is necessary (see events & equipment). At conferences the most common equipment are interpreter booths for 2 or 3 interpreters with interpreting consoles, microphones and headphones). At some smaller and shorter events a mobile interpretation system can could be a better and cheaper option.