Beam stability is more and more crucial with the progress in focusing optics. Mechanical vibration and stability are essential for this beam stability. What’s the present situation in terms of vibration and what are the perspectives to improve the mechanical stability are the objective of this presentation.

 Fundamental aspects in vibration measurements will be highlighted in a comprehensive way : temporal and frequency domain, sensors, data acquisition systems, mostly used quantities and their conversions. Ground vibration in the ESRF site will be presented to show most remarkable characteristics. Traffic generated vibration and vibration influences of tramway line-C extension will be addressed. Vibration of mechanical structure, such as vibration response, resonant frequency and modal analysis, will be presented with some examples. Vibration damping and attenuation techniques will be analyzed through some experiences. Beam stability (e-beam and X-ray beam) will also be addressed. Results on vibration measurements on the experimental hall slab will be presented. Some plans and actions will be proposed to identify vibration sources, to reduce vibration levels.