Added to following to the end of the Architectural Background. Loose integration using the SOA style assumes careful definition of security requirements between partners. Size of transactions, costs of failure to perform, confidentiality agreements, information stewardship, and even changing regulatory requirements can require similar transactions be expressed within quite different security contexts. It is a feature of the SOA approach that security is composed in to meet the specific and evolving needs of different markets and transactions. Security implementation must be free to evolve over time and to support different needs. Energy Interop allows for this composition, without prescribing any particular security implementation.