An Information Sharing and Analysis Center (ISAC) is an organization that provides a central resource for gathering information on cyber and related threats to critical infrastructure and providing two-way sharing of information between the private and public sectors.

[1][2] Sector ISACs began forming in 1999, subsequent to the May 22, 1998 signing of U.S. Presidential Decision Directive-63 (PDD-63), when "the federal government asked each critical infrastructure sector to establish sector-specific organizations to share information about threats and vulnerabilities.

"[3] Decision Directive-63 (PDD-63) was replaced by Homeland Security Presidential Directive 21 in 2013.

European Energy - Information Sharing & Analysis Centre (EE-ISAC)[6] is a network of private utilities, solution providers and (semi) public institutions such as academia, governmental and non-profit organizations which share valuable information on cyber resilience to strengthen the cyber security of the European Power Grid.

In India, the Information Sharing and Analysis Center (ISAC) operates as an independent non-profit organization that works closely as Public-Private-Partner (PPP) with the apex nodal agency for cyber security, National Critical Information Infrastructure Protection Center (NCIIPC), designated under the IT Act Law 2000.