This year's winner's approach to sustainability covers everything from waste disposal to refurbishing halfway houses

Winner: Wates

Wates recognises that there is more to sustainability than green issues. As well as a zeal for cutting carbon emissions, it has shown serious commitment to social sustainability. It held a special community day, during which it dedicated 8,000 man-hours to improving neighbourhoods across the country through makeovers on hostels, halfway houses and day centres. It has also pledged to help 500 unemployed people improve their skills by 2010 through schemes such as its Building Futures programme (65% of those who have done the two-week course so far have found jobs) and is working with colleges and schools to boost construction skills. Waste remains a key issue for the firm. In 2007, it reduced the amount of non-hazardous waste that went to landfill by 80% and is aiming to hit the zero mark by 2010. Staff have received more than 1,000 hours of waste training and can now boost this with an e-learning tool.

Runners up

Bovis Lend Lease

This contractor is pushing hard on sustainability. Targets for 2010 include cutting waste that goes to landfill by 70%, achieving a BREEAM rating of “very good” on all projects worth more than £5m, and helping 3,000 people into work through its new non-profit organisation BeOnsite. It has a rigorous timber procurement policy and built the UK's first commercial project to achieve Forest Stewardship Council Chain of Custody Certification, the gold standard in timber accreditation. Its innovation extends to the its product development, too, an example of which is RePlas, the recycled plastic hoarding it uses in place of timber.

Carillion

Carillion has maintained its sustainability focus this year, in spite of major changes at the firm, including the integration of Mowlem and Alfred McAlpine into the business. Notable achievements include cutting its carbon footprint by 15% per £1m of UK revenue, and delivering a waste neutral construction scheme, which reduced net waste by 253% and saved about £280,000. The firm is also trying to help suppliers boost green policies through an eco-friendly supply chain partnership and has supported dozens of homeless people in finding employment.

Sir Robert McAlpine

As a founding member of the London Climate Change Agency and the UK Green Building Council, this firm is something of a sustainability veteran. It has a systematic approach to green issues - a dedicated member of staff is put in charge of environmental issues on every project and subcontractors are required to report monthly on waste reduction steps and provide transport logs. Eco-friendly projects include the Walkergate School in Newcastle, part of the Building Schools for the Future programme, where 100% of materials from the demolished building have been recycled or reused.

Skanska

Last year's winner, Skanska, has continued to raise its game. Notable is its eagerness to work with other organisations, it is partnering with manufacturer Corus and retail giant Marks & Spencer to improve the sustainability of steel in buildings, and one of its environmental managers was seconded to the government to support the sustainable construction strategy, published in June. It is also working with Job Centre Plus and trade union Ucatt to help long-term jobless people into construction. Internally, it is doing a great job too. Staff receive sustainability reports every six months and the firm has developed its own carbon calculator.

Willmott Dixon

This firm is setting an example with ambitious eco targets. It plans to be carbon neutral by 2012 and send no waste to landfill by the same year. It believes the way to achieve this is from the bottom up. To that end, in-house sustainability consultant Re-Thinking is putting employees through their paces with an online training course, compulsory for all 900 staff members. It also runs workshops on sustainable procurement for its supply chain and clients. Its purchasing policy includes a commitment to buying timber from accredited sustainable sources and even Fairtrade branded coffee for site workers.