By Jorn Madslien
Business reporter, BBC News, Geneva motor show
Toyota and Honda are ahead when it comes to less polluting cars
Green technology is high on the agenda as the car industry gathers for its annual jamboree in Geneva.
A string of new models on display shows how Europe's carmakers are desperate to clean up their act in response to regulatory pressure and changing consumer tastes.
Mercedes and BMW, which have both come under attack because their car fleets emit higher than average levels of CO2, are fighting back with green initiatives.
But Japan's Toyota and Honda are still well ahead of their German rivals, not least with their plans to kit out sporty models with less polluting petrol-electric hybrid engines.
Europe's small carmakers, most notably Fiat, are also benefiting from a gradual shift towards fuel efficient cars.
And, paradoxically perhaps, both Renault and Volkswagen are taking advantage of this shift towards smaller cars by launching larger versions of their most popular models.
On display at the show is the VW Golf estate and a Renault Clio estate concept car.
But some of the large cars on display are equally crucial.
Arch rivals Ford and Opel (Vauxhall) are both unveiling key models that must stand up against each other and fend off other competitors.
Ford's new Mondeo and Opel's forthcoming Vectra replacement concept, the GTC, are both about to be launched into a shrinking market.
This market segment has gradually eroded as traditional customers have been making a shift towards people carriers, crossover vehicles, sports utility vehicles or smaller cars.
"In the past, customers bought cars on a rational basis," observed General Motors marketing boss Alain Visser at the GTC launch party in Geneva on Monday night.
"We want to add some emotional reasons for buying [the forthcoming Vectra replacement]."