The need for companies and the public sector to cut costs has helped keep Carillion's order book healthy, the support services group said today, reporting a strong performance in the first five months of the year.The pipeline of opportunities remains strong, the company said, adding that it is benefitting from the need of private and public sectors to outsource work in an effort to reduce costs.'We remain confident that as we move through 2011 and into 2012 this trend will accelerate in the public sector,' the company said.It said that its Public Private Partnership projects are continuing to perform strongly and that in the Middle East construction services business, the company is now confident that our operating margin in 2010 will be significantly ahead of our original target of at least six per cent, as a result of this year's contract mix.