Researchers produced a neutron beam at the China Spallation Neutron Source (CSNS) for the first time on August 28. The achievement is a milestone for the CSNS project as it marks the completion of main construction and the start of the test operation phase. The national CSNS facility, located in Dongguan, Guangdong Province, should be fully completed and open to domestic and international users by 2018, as scheduled.