The 307's platform is a development of its predecessors', and was shared with sister company's Citroën Xsara . However, the car is much larger than the 306 in every direction.
The 307 continued the company's new styling theme first seen on the Peugeot 206 and Peugeot 607. With upswept front lights and a steeply rising bonnet leading to a highly sloped windscreen, the 307 was a huge departure from its predecessor and re-emphasised the departure from the elegant styling, and sometimes Pininfarina-like design, themes employed on the previous two generations of Peugeots which were first seen on the Peugeot 205, and ended with the Peugeot 40.