Capita Group, the parent of property and infrastructure consultant Capita Symonds, reported a turnover of £845m for the six months to 30 June, up 23% on last year.

Pre-tax profit was £85.1m, up 21% on last year’s figure of £70.1m.

In his chairman’s statement, Rodney Aldridge said Capita Symonds was now the fifth biggest multidisciplinary consultant in the UK. However, he also noted that the subsidiary’s margins were lower than last year because of the company’s withdrawal from the Dubai Rapid Road Link project.

The margins are expected to recover in the second half of the year.

Capita – which is essentially an outsourcing group – also confirmed Aldridge’s resignation from the company on 31 July. Eric Walters, who has been a director at Capita for five years, will replace Aldridge.

Under Aldridge’s chairmanship, the group has grown from a start-up in 1984 to a FTSE 100 company today. Staff numbers have risen from 98 to 26,000, and it now has a client base of 25,000 organisations across the UK.

• Cintra, the transport infrastructure subsidiary of BAA’s probable new owner Ferrovial, reported a 23% increase in revenue to £266.3m in its interim results.