Four entities representing the federal government, the aerospace and defense industries, the biopharmaceutical and healthcare industries and higher education in the US are joining forces to increase business and government use of an existing information infrastructure used for the trusted exchange of confidential information over the Internet. The four entities, which will operate under the name 4BF (Four Bridges Forum), represent the US’s leading Public Key Infrastructure (PKI) Certification Authority bridges. They are the Federal PKI Architecture, which serves the entire range of federal agencies, CertiPath, serving the aerospace and defense industries, SAFE-BioPharma Association, serving the biopharmaceutical and healthcare industries, and HEBCA, serving the higher education sector in the United States. The entities signed a Memo of Agreement using digital signatures based on their individual and interoperable credentials. The 4BF certification bridges establish an infrastructure for the trusted exchange of confidential information and the reliable authentication of identities over the Internet. By providing a highly secure way to validate, trust, and manage identities of unknown participants in an Internet transaction, these bridges are essential to helping achieve the speed, efficiency and cost-savings inherent in use of the Internet for business transactions. This technology also improves interoperability across many different systems. Several individual certification bridges have been introduced over the past few years. Many of these bridges have now linked with each other to form a growing global network in which individuals are able to trust the identity of others within the network. Organisations that want to participate through one of the 4BF member bridges must meet certain security, technical, and operational criteria. However, once they are successfully enrolled, they can leverage the identity credentials of any and all bridge members in the exchange of sensitive and confidential information. The 4BF initiative will raise awareness for certification bridges and the advantages of using them. Initial activities include development of background information about the utility and use of certification bridges, a website and a Washington DC event to promote and educate others about certification bridges.