Enteroviruses are small RNA viruses belonging to the Picornaviridae family. At least 65 serotypes have been described, including polioviruses, coxsackieviruses A and B, echoviruses and unclassified enteroviruses. Because of the absence of envelope they are relatively resistant to physical and chemical agents. They are mainly transmitted by the oral-fecal mode, but respiratory and mucosal transmissions are also possible. In humans, enteroviruses have been involved in miscellaneous acute infections and more recently in persistent infections (chronic meningoencephalitis in agammaglobulinemic patients, post-polio syndrome, chronic myocarditis and dilated cardiomyopathy, insulin-dependent diabetes mellitus...). Hypotheses in the relation between enterovirus persistence and chronic infections are formulated. The virological diagnosis of enterovirus infections is discussed, with a special focus on genomic application techniques (PCR) that are renewing the interest for this family of viruses in clinical pathology. If the role of enteroviruses in chronic pathologies is confirmed, the development of new therapeutic approaches (including vaccines and antiviral agents) will be needed.