[What happens when mmHg are replaced by kPa? (author's transl)]

Resolution no. 30.39 of the WHA, passed in May 1977, recommends the adoption of SI units by the medical community throughout the world, including a change from mmHg to kPa. In Austria this requirement has been law since January 1978. This paper describes how simply the transition can be made and how other results, such as those of tonography and differential tonometry, are numerically altered as a result. Finally a simple modification is described which enables the Goldmann tonometer to indicate intraocular pressure, its kPa being equal to g on the scale.