The invention relates to the field of genetically engineered viral vectors, more specifically to adeno-associated virus (AAV) vectors, for use in gene therapy. The present invention provides a process for the production of high titer recombinant adeno-associated virus vectors that are essentially free of helper virus such as adenovirus. The invention provides an adeno-associated virus (AAV) packaging cell having been provided with nucleic acid encoding a gene product providing AAV helper function allowing generating recombinant AAV without concomitant helper virus production.