Provided are soluble neutral active Hyaluronidase Glycoproteins (sHASEGP's), methods of manufacture, and their use to facilitate administration of other molecules or to alleviate glycosaminoglycan associated pathologies. Minimally active polypeptide domains of the soluble, neutral active sHASEGP domains are described that include asparagine-linked sugar moieties required for a functional neutral active hyaluronidase domain. Included are modified amino-terminal leader peptides that enhance secretion of sHASEGP. Sialated and pegylated forms of the sHASEGPs also are provided. Methods of treatment by administering sHASEGPs and modified forms thereof also are provided.