Postweaning multisystemic wasting syndrome (PMWS) was initially described in 1991 in Saskatchewan (Canada) and has now been described in all continents rearing pigs but Oceania. Porcine circovirus type 2 (PCV2) is the aetiology of this disease, which has also been called porcine circovirosis in some countries. Although the full spectrum of clinical signs and lesions observed in natural cases of PMWS is very difficult to reproduce under experimental infections using PCV2 alone, little doubt exists on the causal relationship between the virus and the wasting syndrome. Furthermore, the clinical and pathological scope of PCV2 infection has been expanded since 1991, and it has been implicated in other conditions: reproductive disorders, porcine dermatitis and nephropathy syndrome (PDNS), the so-called porcine respiratory disease complex (PRDC), proliferative and necrotising pneumonia (PNP), and congenital tremors. The role of PCV2 in these conditions has not been fully clarified and, in some of these cases, it remains as a controversial issue. The objective of this presentation is to review some practical aspects of PMWS.