Porcine circovirus type 2 /PCV2) is considered the essential infectious agent of postweaning multisystemic wasting syndrome (PMWS), a global swine disease of devastating economic and animal welfare impact. Most pigs become infected with PCV2 during their life, but only a proportion of them develop PMWS (1). PMWS is associated with a high PCV2 load, and a general threshold of 10 7 copies of PCV2 per ml serum has been suggested for PMWS diagnosis (2,3). The objective of this study was to compare the performance of two different real-time quantitative polymerase chain reaction (qPCR) assays for PCV2 used routinely in two laboratoires located in Denmark (lab 1) and Spain (lab 2), respectively.