Abstract
The worldwide march to electron storage rings with diffraction-limited photon properties in the X-ray regime is well underway. First out of the gate is MAX-IV in Sweden, scheduled for operation in 2016, followed by SIRIUS in Brazil in 2018; both are greenfield rings operating at 3 GeV with ~520 m circumference and emittances of ~250 pm-rad. They will be followed by the upgrade of ESRF, operating at 6 GeV with a target emittance of 150 pm-rad and operational date of 2020. The upgrade of the APS at Argonne National Laboratory (6 GeV, 60 pm-rad) is anticipated to follow shortly thereafter.