How do the walls of an open organ pipe vibrate when blown? Two geometrically similar open organ pipes are made of different alloys and tooled in different ways. Using a scanning laser Doppler vibrometer the operational deflection shapes (forced modes of vibration) for the first three harmonic partials of the blown pipes are measured. The upper lip is further investigated for the five first harmonic partials. The results are compared and related to the sound intensity distribution from the pipes. This comparison shows that the vibration modes of the structure are dependent upon the material of the pipes. Both the amplitude and the shape of the vibration differ between the pipes. It is found that the vibration amplitude is low for the fifth harmonic partial. For this partial the sound intensity emitted from the mouth also is low.