Support services and construction group Interserve said its full-year saw strong growth despite challenging conditions in some of its markets.Revenues increased 32.8% to £2.9bn, but profits before tax fell 9% to £61.9m, driving earnings per share to decline from 39.1p to 32.2p.The fall in profits was driven by the acquisition of Initial Facilities and the Employment & Skills Group during the year of 2014. However, headline pre-tax profit rose 31% to 106.2m.Interserve said its international construction was affected by challenging conditions as the competition remained high. As a result, volumes increased slightly by 1%, but the order book still grew 37% compared to the previous year.The UK business performed well despite a backdrop of improved demand and an increase in supply chain pressures, with revenues up 21% to £970.7m.The group increased its dividend by 7% to 15.5p, showing confidence in the business.Chief executive Adrian Ringrose said: "2014 was a landmark year for the business in which we advanced our strategy and delivered 35 per cent operating profit growth including strong organic growth despite continuing challenging conditions in a number of our markets."Looking to the future, we are encouraged by the growth potential of the business."Also on Thursday, non-executive chairman Lord Blackwell announced he is due to step down from his role in 2016. The group said it will undertake an external search for a new chairman.Shares in Interserve were up 3.12% to 574.38p on Thursday at 08:16.