March 14, 1984: “Planning Study for Advanced National Synchrotron-Radiation Facilities,” sponsored by the U.S. Department of Energy (DOE) Office of Basic Energy Sciences (Peter Eisenberger and Michael L. Knotek, co-chairs), gives first priority to construction of synchrotron-radiation facility optimized for insertion devices

July 24, 1984: “Major Facilities for Materials Research and Related Disciplines” report, sponsored by the Major Materials Facilities Committee of the Commission on Physical Sciences, Mathematics, and Resources of the National Research Council (Dean E. Eastman and Frederick Seitz, co-chairs), gives highest priority to construction of facility to provide undulator radiation in the hard x-ray region of spectrum

February 1986: “6-GeV Synchrotron X-Ray Source Conceptual Design Report” published by Argonne National Laboratory

April 1987: “7-GeV Advanced Photon Source Conceptual Design Report” published by Argonne National Laboratory

May 1988: DOE approves new-project start

October 1, 1989: First construction funds released by DOE

June 4, 1990: Groundbreaking ceremony and start of Advanced Photon Source facility construction

October 7, 1993: Begin linac commissioning (50-MeV electron beam)

April 17, 1994: First electron beam stored in particle accumulator ring

July 31, 1994: Linac positron-current performance specifications met

January 22, 1995: First 7-GeV electron beam attained in booster synchrotron

February 20, 1995: First injection of 7-GeV electron beam from booster synchrotron to storage ring

March 18, 1995: First turn of 7-GeV electron beam in storage ring

March 25, 1995: First stored electron beam (4.5 GeV)

March 26, 1995: First storage ring bending magnet radiation detected in Sector 1 (beamline 1-BM-A)

April 15, 1995: First stored 7-GeV electron beam

August 9, 1995: First x-ray beam from Advanced Photon Source undulator in Sector 1 (beamline 1-ID)

October 11, 1995: Attain DOE storage-ring commissioning milestone of 20-mA operation, minimum 10 hours of beam lifetime

January 12, 1996: First 100-mA stored electron beam

January 26, 1996: First undulator operated with 100-mA stored electron beam

May 1, 1996: APS dedication ceremony in experiment hall

July 30, 1996: First stored 7-GeV positron beam

July 31, 1996: First stored positron beam at 100-mA current

August 8, 1996: Secretary of Energy signs Key Decision #4 - project completion milestone