Ben Griffiths (pictured), a director who joined in 2016 and was last year seconded to Airbus UK as head of communications, is to leave Powerscourt later this month to join aviation support company 2Excel Aviation as head of communications.
Former Sunday Times journalist John Elliott left in May after eight years as senior consultant to return to the newspaper as deputy head of editorial and social media for the Sunday Times Fast Track.
Another senior consultant, Niall Walsh, joined e-cigarette company JUUL Labs in July as external comms manager for EMEA.
Former Powerscourt consultant Isabelle Saber has joined Brunswick as account director. Another former consultant, Sofie Brewis, left in May to work for Prosek Partners in New York as an account supervisor.
It's understood another former Powerscourt employee has also departed in the past couple of months.
Appointments this year have included David Lloyd-Seed, former director of investor relations at Telefonica UK and ex-Tulchan partner, who joined in April as head of capital markets.
MHP veteran James White left that agency earlier in 2019 to head Powerscourt's Industrials practice.
Other more recent additions have included senior consultants Jessica Hodgson, previously of Consilium, and Donjeta Miftari, who joined from the Institute of Directors and was included this year's PRWeek UK 30 Under 30.
Powerscourt, which was founded in 2004 by former Sunday Times business editor Rory Godson, grew revenue 24 per cent to £9.9m in 2018, according to the most recent PRWeek UK Top 150 Consultancies report. It currently employs 55 people in London and five in Dublin.
David Cohen, chief operating officer at Powerscourt, said: "Powerscourt had a record year in 2018 in terms of revenue generation and we continue to invest in attracting excellent staff to meet that demand, with 17 new additions so far in 2019.
"Strategically, we have continued the process of expanding our service offering into corporate campaigning, investor relations, political intelligence and data & insight. The first half of 2019 has seen a number of client wins across the full range of our service offering, including Bovis Homes, Brown Shipley, CarTrawler, Draper Esprit and Zurich Insurance, and we are on track for another very successful year."