The 2011 Porsche Boxster gets a relatively high safety score, even though crash-test results aren't forthcoming.
Neither the National Highway Traffic Safety Administration (NHTSA) nor the Insurance Institute for Highway Safety (IIHS) has put the Boxster through their sled tests. The addition of a roof-crush test to the IIHS' schedule, and the revision of the NHTSA star scale, probably aren't the hold-up in this case--the Boxster's high price and low sales figures are more likely the reason it hasn't been crash-tested.
The Boxster benefits from a good assortment of safety features, even without the gadgety bits like lane-departure warning systems and adaptive cruise control. Anti-lock brakes and stability control, are standard; dual front and side airbags are, too. The side airbags in the Boxster do some of the work that curtain airbags would in a coupe--they're larger than usual, are mounted in the door sills, and offer a measure of head protection usually unavailable in a convertible.
There's no option for a rearview camera, which is being studied by the NHTSA for a possible safety mandate in 2014. The Boxster does offer optional parking sensors, which can help mitigate the reduced visibility to the rear quarters.