Simultaneous Interpretation – How it Works

March 4, 2024
Simultaneous Interpretation – How it Works

I believe that simultaneous interpretation is one of the most challenging language services to provide. The simultaneous interpreter has to be incredibly quick-thinking and needs a superb command of the two languages with which they are working, including any specialist jargon. As a result, simultaneous interpretation is one of the most mentally taxing tasks I can imagine when it comes to working with language. 

Simultaneous interpreting is a huge topic and there are some excellent books out there if you’re really taken with the concept. For now, I’m going to give you a run-down of what simultaneous interpretation is, how it works, why simultaneous interpreters are used and what specialist equipment is involved. 

Let’s start with a simultaneous interpretation definition. 

What Is Simultaneous Interpretation?

Simultaneous interpretation requires live translation from the source language to the target language. Unlike consecutive interpretation, where the speaker pauses every sentence or two to allow the interpreter to translate, simultaneous interpretation keeps pace with the speaker through active listening, analysis, and translation in real time. We’ll look at some use cases below, including UN hearings, EU meetings, and international conferences, among others.

This definition, for me, really encapsulates the huge challenge that simultaneous interpreters face. They must deliver the speaker’s last sentence in another language while also listening to the next sentence, so that they can be ready to interpret that one as well. And the next, and the next. It’s a skill that I have plenty of admiration for; it’s certainly not something that everyone can do. 

Also sometimes referred to as simultaneous translators, simultaneous interpreters have to be exceptionally good listeners. They need to hear, analyse and reproduce the speaker’s words in another language, all in real time. Simultaneous translation also requires a high degree of cultural awareness, so that the translated words can be delivered in the right way. 

When is Simultaneous Interpretation Applicable?

What is simultaneous interpreting used for? Organisations use it to enable people to listen to a speaker in real time, despite the listeners not understanding the language the speaker is using. The allows communication to flow across linguistic divides. 

Pros and Cons of Simultaneous Interpretation

There are both pros and cons when it comes to simultaneous interpretation. Shall we take a look at a few of them? 


The biggest advantage of simultaneous interpreting is that it allows the speaker to deliver their words naturally, without having to keep stopping and starting while the interpreter catches up (as happens with consecutive interpretation). 

Simultaneous interpretation techniques also mean that the audience is able to benefit from the speaker’s gestures and other non-verbal cues, as they are able to listen with a delay of just a few seconds. This benefits both the speaker and the audience by increasing the impact and effectiveness of the communication.  

Another plus point of simultaneous translation is that it can be used to deliver messages where speed is of the essence. In emergency situations and disaster response zones, the timely delivery of safety information can save lives. Simultaneous interpreting allows this to happen in multiple languages, without delay. 


Simultaneous interpretation is built around the premise of there being a presenter and an audience. It is not suited to two-way conversations (that’s what consecutive interpretation is for). As such, events such as conferences that use simultaneous interpretation to deliver speeches may struggle to facilitate a question and answer session when the speaker finishes. 

The other major con is that simultaneous interpreting is a costly service to provide. Given the taxing nature of the work, simultaneous interpreters tend to work in pairs, meaning you’ll need to pay two people for each language that you wish to deliver the speech in. Each interpreter can work for about 20-30 minutes before they will need a break. Any longer than that and their focus – and thus the quality of the interpretation that they are delivering – may well wane. 

This means that if you’re organising an event in (for example) Europe, then your simultaneous translation costs can very quickly mount up. 

The need for dedicated interpreting booths and headsets further adds to this cost, as well as meaning that venues need to be carefully considered to ensure they have the right facilities (although there are some mobile solutions that can help with this – I’ll talk more about those below). 

Ideal Scenarios/Use Cases

I think the best example of simultaneous interpretation is the meetings held at the European Union. Participants from the 27 member states are able to discuss and debate matters of vast importance with ease, thanks to the presence of simultaneous interpreters. If you’re looking for interpretation services, this is very much the gold standard. 

Many other use cases exist. We mentioned above the delivery of safety information in emergency situations. This can be done at press conferences, town hall meetings and via live television broadcasts. 

Conferences and other big events, meanwhile, use simultaneous interpreters in order to open up attendance to delegates of multiple nationalities. From global health conferences to the latest tech events, these large-scale meetings can share best practice, discuss innovation and deliver case studies to delegates who speak different languages, all thanks to simultaneous interpreting. 

Smaller events often make use of simultaneous interpretation as well. Guided tours, academic lectures, religious events… all of these and more are able to reach out to larger audiences if they use a simultaneous interpreter to present the event in another language. 

Equipment and Requirements for Simultaneous Interpretation

I mentioned above that simultaneous interpretation isn’t the cheapest of language services. There are two elements to that cost. The first is that you need two very talented linguists for each language you wish to deliver. The second is that you’ll need a venue with specialist equipment or else a sufficient supply of portable equipment. 

Let’s take a look at what you’ll need to facilitate the smooth delivery of simultaneous interpretation services. 

General Setup and Standards

To enable effective simultaneous interpreting, you’ll need to create an environment in which the interpreters can work free from distractions. They will need to be able to hear clearly what the speaker is saying and to focus on translating without having to block out background noise. There are various ways to achieve this through the use of specialist equipment. 


Simultaneous interpretation is relatively simple to set up, provided you have the right equipment. The bare essentials include a set of receivers with headphones for the listeners, a transmitter and a microphone and a pair of headphones for the interpreter. 

The interpreter listens to the speaker through their headphones. They then provide the simultaneous translation by speaking into a microphone. The transmitter sends the translation from the microphones to personal wireless receivers and the audience listens through their headphones. 

Often, the simultaneous interpreter is provided with a soundproof booth in which to work. These booths are large enough to seat two people, so that the interpreters can work in pairs. Large conference centres will have fixed booths in place, but mobile solutions are also available. For a price. The booths will need to be positioned so that the interpreters can see the speaker, with one booth per language.  

Base transmitters (also known as table transmitters or stationary transmitters) tend to be used for a booth setup. They are fixed to one point, so are ideal for simultaneous interpreters who are working from booths. 

Portable transmitters (also called belt-clip transmitters or tour-guide transmitters), meanwhile, can be used in situations where the interpreter needs to move around, for example during a guided tour of a museum. 

Whether you’re using stationary or portable transmitters, you’ll need to allow one transmitter per language (for FM setups). 

The Simultaneous Interpreter

With your equipment set up properly, all you need is the perfect simultaneous interpreter in order to deliver your speeches or presentations in multiple languages. So, what skills or character traits should you be looking out for? 


I’ve worked with many highly talented interpreters over the years, all of whom have exhibited certain core skills. These include:

  • The ability to speak two languages fluently. There’s no leeway here – the simultaneous interpreter needs to speak both tongues with native ability. 

  • Specialist knowledge of industry terms. This is essential for speeches that include a lot of legal jargon, technological references or medical terminology, for example. An extensive vocabulary is a must. 

  • Active listening skills. Simultaneous interpretation techniques involve listening with all the senses and with full concentration. This is one of the reasons that simultaneous translators need regular breaks between bouts of interpretation. 

  • Outstanding memories. Again, this is non-negotiable. Simultaneous interpreters need to have superb short-term and long-term memories in order to perform effectively. 

  • Multi-tasking skills. Listening to somebody talk at the same time that you’re talking yourself isn’t easy, even before you add in the complexity of the fact that simultaneous interpreters also need to translate what they’re listening to. As such, the simultaneous interpreter has to be an exceptional multi-tasker. 

  • Cultural awareness. This is key to ensuring that you use the right language and tone to convey the speaker’s message effectively to the target audience. 

Training and Certifications

Simultaneous interpreters need to train hard to establish their skills, with various certifications available to prover their abilities. These include:

  • MA in Interpreting/MA in Interpreting and Translation/European Masters in Interpreting – a qualification at this level is often viewed as the bare minimum that’s required for a simultaneous interpreter to find work. 

  • Foundation Certificate in Interpreting – this diploma allows individuals who speak two or more languages to discover the basics of interpreting. It can be an excellent stepping-stone to… 

  • The Chartered Institute of Linguists Diploma in Public Service Interpreting (DPSI). This qualification is focused on those seeking to become interpreters in the fields of medicine, law and/or local government. The qualification allows interpreters to focus on English law, Scottish law, Northern Irish law, health and local government. Equivalent qualifications are available in other countries, with each suited to the particular location’s requirements. 

  • Professional training and development events – continuing professional development (CPD) events allow simultaneous interpreters to keep their skills up to date and to hone their craft. 

Simultaneous Interpretation Today

Many industries evolve over time and the simultaneous interpretation sector is no exception. As such, simultaneous interpreters need to ensure that the services they provide fit with clients’ ever-evolving requirements. 


Various factors can serve to get in the way of simultaneous interpretation delivery. Extreme weather, pandemics, rail/air strikes… all of these can act as restrictions on the delivery of simultaneous interpreting. Thankfully, with the rise of new technologies, remote simultaneous interpretation provides a solid solution where it’s not possible for interpreters to be physically present in the same location as those with whom they are working.  

The Usage of Video Conferencing Platforms

This is where the usage of different video conferencing platforms proves essential. For example, Zoom interpretation services allow meeting and webinar organisers to choose the languages that their attendees can listen in. In just a few clicks, they can allow participants to access live interpretation of the meeting/webinar, using up to five languages per video call. 

Using a video conferencing platform in this way is ideal for organisations looking to reduce their interpretation services spend, though you will need a paid-for version of Zoom to start using this functionality. 

Other Forms/Variations of Interpretation

Simultaneous interpretation is not the only service that you can use to translate spoken language. If you would like to learn more about other interpretation types, click the link below. Suffice it to say here that you can choose from:

  • Simultaneous interpretation

  • Consecutive interpretation

  • Whispered interpretation

  • Relay interpretation (either simultaneous or consecutive) 

  • Liaison interpretation 

  • Escort interpretation 

  • Travel interpretation

  • Over-the-phone interpretation

  • Remote video interpretation

Read more: What are the different types of interpretation?

Wrap Up

I hope that you’ve gained some valuable insights from this article. Simultaneous interpreting is such a fascinating topic. Remember, in this post we’ve covered:

  • The simultaneous interpreting definition

  • Uses of simultaneous interpretation, along with its pros and cons

  • Details of the equipment that simultaneous interpreters need in order to work effectively

  • The skills that simultaneous translators need and how they can evidence these through training and certifications

  • Other forms of interpretation that you may need

Simultaneous interpretation can be a huge help when it comes to growing your organisation and connecting with audiences who don’t speak your language. How will you be using it to advance your success? 

By Ofer Tirosh

Ofer Tirosh is the founder and CEO of Tomedes, a language technology and translation company that supports business growth through a range of innovative localization strategies. He has been helping companies reach their global goals since 2007.



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