Volvo says the primary engineering challenge was to get the same safety in the S40's small package that's in the flagship S80 sedan. To that end It has been designed using something called VIVA, for Volvo Intelligent Vehicle Architecture. What appears to be an unprecedented amount of time, research, testing and detail has gone into the construction of the chassis and body in the interest of crash protection. There are several zones of deformation upon impact, built with different strengths of steel depending on that zone's function: conventional, high strength, extra high strength and ultra high strength steel.

The S40 was launched as a 2004 1/2 model in January 2004, but it's essentially a 2005 model. The previous S40 line (2004 and older) was vast and the new S40 line will likewise grow over the next couple of years. The all-new 2004 1/2 models come with front-wheel drive and a five-speed automatic; 2005 models offer all-wheel drive and a six-speed manual gearbox as well. Also available for 2005: a V50 sport wagon.