The Quadrilateral Security Dialogue (QSD), commonly known as the Quad, is an informal strategic security dialogue between

Australia, India, Japan and the United States that is maintained by talks between member countries. 

Since March 2021, member states of the Quad and their leaders have hosted regular “Leaders Summits”, which have been both online and in-person. 

The Quad is seen as a way for the four countries to cooperate on security issues in the Indo-Pacific region.  

The Quad has been criticized by some for being a "containment" strategy against China. 

Recently Australia has ruled out holding a Quad summit in Sydney without the participation of U.S. President Joe Biden. 

The summit was scheduled to take place on May 24 in Sydney 

but Biden has canceled his trip to Australia due to the ongoing debt limit negotiations in the United States. 

Australian Prime Minister Anthony Albanese said that he understands why Biden has canceled his trip 

but that he is disappointed that the Quad summit will not be able to take place in Sydney.  

The cancellation of the Quad summit is a setback for the Biden administration, but it is not a major blow.