Varicella­zoster virus (VZV), or human herpes virus type 3, is a member of the Herpesviridae family. VZV causes varicella (chickenpox) as primary infection which is a highly contagious epidemic disease globally. VZV reactivation from latency results in herpes zoster (shingle) which is a painful skin disease. Japan and the United States started to vaccinate all children in 1987 and 1995 respectively, which has reduced varicella­related morbidity and mortality significantly. However, adverse events following administration of vaccine occur occasionally including secondary transmission and breakthrough infections. The research for safer VZV vaccine has been progressing with foreseeable advances.