A document exchange based on user-definable validation rules provided by the exchanging parties. In one embodiment, an uploader uploads a document from a first computer, the upload being associated with a first member account registered with a network site. A user interface receives a delivery destination for the document from the first computer, the delivery destination being associated with a second member account registered with the network site. A content validator validates content of the document based on rules registered at the network site in connection with the second member account. An output adaptor determines a document delivery format registered at the network site in connection with the second member account. A delivery component delivers the document in the determined format to a second computer associated with the second member account.