Three crash tests of convex guardrails have been performed at the VTI crash site. Convex guardrails can typically be found at intersections or in the middle of roundabouts. The curved convex guardrail was, as expected, more yielding than the same straight one. Although yielding is a desirable function while thinking impact crash safety, in the hereby shown cases the risk of secondary impact to objects in the area behind the curved guardrail can not be neglected. Measured accelerations are low. It is important for the function that the soil surface behind the guardrail is more or less in level with the carriageway. In the tested configuration, the angled bars connecting the guardrail to ground seems important for good function during impact. The overall result can be summarized as curved guardrails yield more than straight ones, they take advantage of a large are, which must be kept free from hazardous objects, the rod is essential for the function and we did not record any specific hazardous knees on the cross member.