Holidaymakers will soon , for the first time, be able to claim to be saving the planet, under plans unveiled in Portugal last week.
An unprecedented green giant tourist resort - with 30,000 beds but emitting little waste and none of the pollution that causes global warming - is scheduled to open in three years' time near the coast south of Lisbon. The £670m project - the first of a series around the world - is designed to pioneer environmentally friendly living.
It is drawing on the unlikely example of a former sink housing estate in the south London suburb of Wallington - an offbeat British import to a country which will host our football fans for this summer's Euro 2004 tournament.
The Mata de Sesimbra resort, planned to cover 13,000 acres, is being launched by the international conservation group WWF and the British environmental group Bioregional, in an area scarred by disused quarries and diseased pine forests.
Due to be developed by a Portuguese property development company - and endorsed by the European Commission and the British government - it is designed to replace plans for 11 traditional, environmentally damaging, resorts in the area.
WWF estimates that tourism to the Mediterranean will rise by 50 per cent to reach 350 million people a year in 2020. "It is eating into our natural capital", says Dr Claude Martin, the group's international director general. "New models such as Mata de Sesimbra are vital."
The group is launching the resort to demonstrate how Europeans can reduce their "ecological footprint", the impact they have on the planet. It estimates that if everyone in the world lived as Europeans now do, humanity would need three Earths to provide the necessary energy, resources and agricultural land.
The resort is modelled on BedZED in Wallington, a former sink housing estate turned into a futuristic model of ecological living. Developed by Bioregional, the 82-home estate burns no fossil fuels and - through innovative design and energy conservation - uses half as much energy of all kinds as normal. It recycles its water and the families share cars communally.
The resort will be powered completely by renewable energy, produce only a 20th of the normal amount of waste, and dramatically cut its use of water by collecting rain and recycling waste water.
Half of the materials used to build it will have been recycled and half will come from within 30 miles, to reduce transport pollution.
Half of all the food served in the resort will be grown locally, and most of the resort's area will be devoted to an 11,800-acre nature reserve.
Traditional cork oak and umbrella forests will be planted, in one of Europe's biggest single re-forestation projects.
WWF and Bioregional plan to make this the first of five to 10 sustainable communities, each serving some 5,000 people, in the USA, China, South Africa, Australia and other European countries.