Greenpeace is usually associated with direct action rather than dialogue. But sometimes one can change into the other, and that is what happened when the campaign group challenged Unilever to change its refrigeration technology. The result was a continuing relationship that has helped both parties achieve their goals.

"It was rather confrontational at first, but we moved from confrontation to partnership," says Alan Gerrard, Unilever manager responsible for a project to introduce ice-cream cabinets that do not make the world hotter but still keep ice cream cold.