Publisher is responsible for the producing and/or printing costs and the content of the publication. ISBN is assigned according to the publisher. The name of the publisher should be printed in the publication.

It is the duty of the publisher to obtain an ISBN or ISMN for its publications. The publisher is responsible for the identifiers of the publications it produces. The same identifier cannot be assigned to another publication, even if the earlier publication has sold out.

In the ISBN and ISMN system, any person or organisation publishing books or notated music publications intended for public use is considered a publisher. This means that publishers include: