The next-generation 911 cabrio has been spied testing, ahead of its launch in 2011.
The 998 will replace the current 911, which itself has only just been refreshed, and Porsche is promising the car will be far more competent than its predecessor.
The biggest alteration appears to be the wider track, disguised by the fake turbo-style vents in the rear bodywork, aimed at improving high-speed agility.
The front lights are said to be slightly more upright, harking back to early 911s, to appease safety regulations. The exterior mirrors are now mounted on the doors, rather than the front of the side windows, possibly to improve rear visibility. The plastic trim that runs along the edges of the roof, evident on the 997, has also disappeared.
Porsche is also thought to be working on a radical aerodynamic package, with a prominent lip added to the rear spoiler, presumably for added downforce and extra cooling of the engine bay.