by Malcolm Hyde, regional director of the CBI South East

There is a group of companies that employ nearly five million people and generate over £1 trillion in revenues every year.

I’m sure you would agree that they should be properly nurtured.

Yet they have been undervalued and under-acknowledged by government, business and media for years.

The companies I am taking about are the UK’s medium-sized businesses (MSBs) – employing 50 to 499 people with a turnover of £10m to £100m.

They do not get the support that small businesses get, or the headlines of the large, but they play a huge role in the economy.

Perhaps it is unsurprising that they get little attention – after all, they make up just under 2% of the business population.

These companies – which exist in every sector and every part of the country – have been the main engine of the recovery, significantly contributing to jobs and growth across the UK.

There are some impressive facts. MSBs employ 16% of the workforce and generate nearly a quarter of private sector revenue in the UK.

They were responsible for creating nearly a third of private sector jobs between 2010 and 2013. In the same period their total turnover grew by 7% – compared with less than half that for large companies.

Their contribution to the UK economy is estimated to be over £300 billion GVA (Gross Value Added) – roughly one fifth of the total.

In the South East, there are over 5,600 of these firms employing more than 700,000 people locally – nearly 30,000 more than in 2010.

However, there is still untapped potential.

CBI research shows that with the right support these MSBs could be worth an additional £20bn to the economy by 2020.

What do we need to do? First, we need to give these companies the ambition and confidence to grow by talking about the vital role they play.

The CBI has established M-Clubs to get leaders of these businesses together to tackle the common challenges they face.

But the government needs to take a lead too. Appointing an MSB to the Prime Minister’s Business Advisory Group would show they are taken seriously at the very top of the government.

CBI research shows that with the right support these MSBs could be worth an additional £20bn to the economy by 2020.

Second, they need to get access to the right finance. The government should help develop a more diverse range of debt capital markets, like private placements and retail bonds to help businesses move away from traditional bank debt.

Third, we need to help them access the innovation and research of universities. The Department for Business needs to set up a one-stop-shop portal to facilitate links with universities, as recommended by the Witty Review.

And finally, we must help these companies access new growth markets. UK Trade & Industry and UK Export Finance must do more to promote their services to firms at a local level, as most aren’t even aware they exist.

The UK’s medium-sized firms have been the main engine of our recovery and already punch well above their weight, contributing almost a quarter of total business revenue. Can government afford to ignore the potential of an extra £20 billion to the UK economy by 2020?

With a small helping hand, their future growth potential could be even greater.