Accelerator physics trends at the ESRF

The operation of third generation synchrotron light sources at design target goals raises a number of challenging problems in accelerator physics. This paper will review the most recent advances made at the ESRF in some of these areas during the first two years of operation. The lattice performance is dominated by the non-linear effects induced by the requirement for a low emittance; the correction of these effects enables significant increase of the tunability and flexibility of the DBA lattice. Solutions to overcome the instability-related problems linked to the increase of intensity thresholds in multibunch and single bunch modes will be discussed. The achievement of a stability of the beam centre of mass in the micron range is a key issue for all third generation light sources. Present ESRF performances and limitations will be presented