This invention has as its object to attain strong security and to implement network solutions with high convenience and simplicity with low cost upon providing Web services. To this end, an information processing apparatus according to this invention has the following arrangement. That is, an information processing apparatus (1400) which includes a plurality of Web services (110 and the like) and a plurality of authentication/authorization services (107 and the like), is characterized by having an XML script unit (104) which holds an XML script (106) that describes association between information pertaining to respective Web services and information pertaining to the authentication/authorization services that execute authentication processing upon providing the respective Web services, and an arbitration service (103) which determines information pertaining to the authentication/authorization service described in association with the Web service requested by the user, and in that when the user is authenticated using the determined authentication/authorization service, the Web service requested by the user is provided.