There are now more than a thousand Web Services [22] offering access to disparate biological resources namely data and computational tools. It is extremely difficult for biological researchers to search in a Web Services (WS) registry for a relevant WS using the standard (primarily computational) descriptions used to describe it. Semantic Biological Web Services Registry (SemBOWSER) is an ontology-based implementation of the UDDI specification, which enables, at present, glycoproteomics researchers to publish, search and discover WS using semantic, service-level, descriptive domain keywords. SemBOWSER classifies a WS along two dimensions- the taskthey implement and the domain they are associated with. Each published WS is associated with the relevant ProPreO (comprehensive process ontology for glycoproteomics experimental lifecycle) ontology-based keywords (implemented as part of the registry). A researcher, in turn, can search for relevant WS using only the descriptive keywords, part of their everyday working lexicon. This intuitive search is underpinned by the ProPreO ontology, thereby making use of the inherent advantages of a semantic search, as compared to a purely syntactic search, namely disambiguation and use of named relationships between concepts. SemBOWSER is part of the glycoproteomics web portal’ stargate’.