The inter-organizational business process is one of the hot issues in B2B e-commerce. In this paper, through the survey of the inter-organizational business process integration and the analysis of B2Bi related standards, e.g., BPML, WSDL, WSCI, and BPSS, we propose a method of linking BPML and BPSS specifications that can be used to integrate private processes with the public processes among enterprises. We also suggest an application example of the method by redefining a PIP of RosettaNet to the BPSS specification. The basic principle of the method is to maintain the independency of the existing BPML and BPSS applications and to construct an intermediary transformation module between the two applications