Whitmey, who joined Discovery three years ago, has been given the position after demonstrating her client services skills on various accounts, including Diageo and Diesel.
MacSherry's background is in financial services and he joins from Claritas, where he was team leader for new business. His 17 years of marketing experience include leading the launch of two consumer segmentation products for Claritas in Ireland.
Both Whitmey and MacSherry will generate new-business leads by working with other Discovery staff and Discovery's sister agency EHS Brann in London and Cirencester.
They will report to client services director Dave Craft, who said: "At Discovery, our strength has always lain with our consultants and the way in which they combine technical expertise with marketing know-how. Tash's long history in data planning and Paul's knowledge of financial services reflect this heritage and enable us to refocus our approach to new business."
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