Taaffe also said "every option’s on the table" for his review of the business, including possible disposals, although he played down the likelihood of this.
On Friday the group reported a 20 per cent fall in pre-tax profits in 2014, a year it labelled "unusually turbulent", featuring the departure of both the chief executive Lord Chadlington and chairman Lord Myners. Like-for-like revenue fell for Grayling, Citigate and Red, although it grew 8.4 per cent at Huntsworth Heath.
Asked about the scope and duration of his strategic and operational review, Taaffe, who joined on 7 April, said: "The chairman has given me 100 days. The reality is I’m going to move in the next 30 days on the obvious things we can do.
"The review will look at the type of clients we have, the type of marketplaces we’re in. Obviously, the value proposition of each one of these companies [will be looked at]. And, of course, the talent we have in those companies. It’s really looking top to bottom at every one of these businesses.
"My fundamental questions are: are we serving the right clients, are there clients that we’re not serving, do we have the right people? I do think there are some great people in a number of these companies."
He added: "I’m looking at a one-year plan and I have no hesitation in believing that all these companies will return to growth, and indeed many of them already have. Huntsworth Health is growing at probably way above market rate."
There had been speculation that global media firms such as WPP and Publicis were considering making an approach for parts of the business in light of Huntsworth’s recent difficulties.
Asked if his review would consider agency disposals or office closures, Taaffe said: "Every option’s on the table but right now it’s more about where you go from here rather than taking anything out. The company has been spending a lot of money building this network. It’s about where it goes next."
Taaffe, who was previously chief executive of Hill & Knowlton and Groupon's comms leader, was positive about his first impressions of Huntsworth.
"The reality is Huntsworth has some great brands that really mean a lot of things to clients. Not all the brands mean enough, but each one of those company’s agencies has a very special value proposition."
Taaffe said the PR industry generally was starting to grow after being "flat for many years". He said many agencies had failed to keep step with client demand, which had "moved quite rapidly", presenting an opportunity for Huntsworth.
Last week Grayling announced the promotion of Jan Simunek to oversee the company’s operations in Western Europe. Taaffe said: "Continental Europe has historically been a bit of an issue for Grayling, but it now has a really good, clear leader."