The vote, which took place yesterday (31 October) saw every partner except one back the deal.
With the merger now formally approved, the deal will be completed on Friday 4 November 2011.
Arcadis is issuing three million shares to EC Harris partners and paying an undisclosed cash amount from existing credit facilities.
EC Harris chief executive Philip Youell said: “I am delighted that our partners have ratified the proposals and we can now proceed to merge with Arcadis. Since announcing our plans we have had an overwhelmingly positive reaction from our partners, people, clients and the market. Arcadis and EC Harris are a natural fit and there is genuine excitement about the opportunities that the merger presents. We will now begin the process of integrating our two firms, with EC Harris retaining its brand within the wider group. I am looking forward to working with our new colleagues at Arcadis to meet our clients’ needs.”
Arcadis chief executive Harrie Noy said: “I truly believe that the leadership position our combined firms have in project management and related consultancy services offers genuine opportunities for expansion in key emerging markets while at the same time giving us a strong base in the well-developed UK consultancy market, a position we have aspired to achieve for many years. We welcome the strength of the EC Harris brand and the leadership they bring to Arcadis and are excited about the synergy opportunities.”
The merged companies will have close to 19,000 professional staff and €2.3bn revenues. EC Harris will continue to operate as a partnership and the EC Harris brand identity will be retained.
EC Harris will take up a company-wide remit within Arcadis for the building sector and take the lead on programme and project management services.