Expertise or expertises?

Do you ever use the word expertises in your English? I often see it in Dutch people’s English CVs, for instance, in job descriptions or on website navigation bars. It seems so handy, but it’s not actually an English word. So what should you write?

Many languages – including English and Dutch – make a distinction between ‘things’ that can be counted (like car, book and bottle) and ‘stuff’ that can’t (such as water, warmth and information). You can talk about a car and about cars, but not about a warmth or warmths).

Although languages generally agree on what is countable and what is not, they don’t always do so – and that gives rise to problems.

Take the English – and Dutch – word expertise (‘the skill, knowledge and judgement of an expert’). In English, this can only be uncountable. That means you can’t talk about an expertise or a number of expertises.

Here are some examples of the correct use of expertise in English:

We use our expertise to deliver better products and services for our customers.
The department is seeking expertise in engineering and landscape design.

If you want to be specific about the type of expertise – where in Dutch you might want to talk about een expertise or verschillende expertises – English uses phrases like area of expertise or field of expertise:

The two agencies will work together in their respective areas of expertise.
My principal area of expertise is talent management, so I focus on that.
Each tutor within the course has a different field of expertise.

Note that if you want to refer to een expertise, in the sense of a report drawn up by an expert, then you need to use expert’s report or expert report in English.