The phrase "a host of clients" is correct and usable in written English.
It can be used to refer to a large number of clients or customers that someone has, often in a business context.
Example: "Our company has successfully built a host of clients over the years, ranging from small startups to large corporations."
Alternatives: "a multitude of clients" or "a large number of clients".
She then established her own production company, directing for a host of clients from Anacin and Bloomingdales to Union Carbide, Robitussin and hundreds more.
Once a political writer for the Chicago Tribune, Axelrod moved on to develop media and communication strategies for a host of clients including John Edwards, Hillary Clinton and Barack Obama.
The Massachusetts-based company has been providing music data to a host of clients in recent years, including Spotify, Rdio, Vevo and Rhapsody, helping them to improve their music recommendations for users.
I was not an immediate convert, although Mallinson points to a host of clients, many of them leading figures from the business world, who have seen their fear evaporate after a single session.
He is responsible for senior level media strategy for a host of clients, C-suite and executive messaging/thought leadership, media training and speech coaching, as well as crisis communications and strategic platforms.
The company also services supermarkets and a host of industrial clients.
Mr. Black is on leave from his firm, which has ties to a host of business clients and several foreign governments.
The escort service accused of enticing Eliot Spitzer and a host of other clients was operated by four improbable masters of temptation: a rejuvenated tax specialist, a boarding school pixie, a literature major from Virginia and a clog-wearing nutritionist.
A Chinese wall supposedly separated research from investment banking at firms like Salomon, but Mr. Grubman was so clearly the principal strategic adviser to a host of banking clients that he attended many of their board meetings.
As a public affairs consultant, he advised The Metropolitan Museum of Art, The Mariners Museumm, and a host of corporate clients, while his amusing and insightful freelance pieces appeared in such national magazines as "Omni," "Conde Nast Traveler," and "Travel & Leisure".
Facing a host of new rules, clients have flocked their way.
