The present invention provides duplexed parvovirus vector genomes that are capable under appropriate conditions of forming a double-stranded molecule by intrastrand base-pairing. Also provided are duplexed parvovirus particles comprising the vector genome. Further disclosed are templates and methods for producing the duplexed vector genomes and duplexed parvovirus particles of the invention. Methods of administering these reagents to a cell or subject are also described. Preferably, the parvovirus capsid is an AAV capsid. It is further preferred that the vector genome comprises AAV terminal repeat sequences.