  We present measurements of the Goos-H\"anchen shift in a two-dimensional
dielectric microwave cavity. Microwave beams are generated by a suitable
superposition of the spherical waves generated by an array of antennas; the
resulting beams are then reflected at a planar interface. By measuring the
electric field including its phase, Poynting vectors of the incoming and
reflected beams can be extracted, which in turn are used to find the incoming
angle and the positions where the beam hits the interface and where it is
reflected. These positions directly yield the Goos-H\"anchen shift. The results
are compared to the classical Artmann result and a numerical calculation using
Gaussian beams.
