As you can see, instead of a fabric top, the new Z4 is following in the footsteps of its 3-Series Convertible big brother, plus its Mercedes SLK rival, with a retractable steel top.

BMW is also looking to out-perform the Porsche Boxster with a new range of powerful engines for the new Z4. These are likely to include the twin-turbocharged 3.0-litre straight six-cylinder unit.

Being based on the current 3-Series underpinnings, there’s even the possibility that the Z4 will be available with diesel power for the first time with punchy twin-turbo 2.0-litre diesel engine from the 123d also likely to feature. Take that TT TDI.

A flagship M model is likely to get the new 4.0-litre V8 from the M3 too.

The new Z4 is likely to go on show at Geneva in March with sales starting in late 2009.