The ARATS and SEF are non-governmental organisations founded in 1991 and 1990, respectively.
ARATS-SEF talks have speeded up since 2008 and produced a number of important cross-Strait agreements, including an agreement to lift the ban on direct shipping, air transport and postal services in 2008 and the long-awaited Economic Cooperation Framework Agreement in 2010.
The meeting between Zhang and Wang, the sitting cross-Strait affairs chiefs from the two sides, is considered an important breakthrough in promoting cross-Strait relations and may lead to regular exchanges of visits in the future.
The two diplomats first met informally on the sidelines of the economic leaders' meeting of the Asia-Pacific Economic Cooperation in Bali, Indonesia, last October when they agreed to hold mutual visits.
In his speech, Wang described his meeting with Zhang as "an unimaginable occasion in earlier years".
"Being able to sit down and talk is a really valuable opportunity, considering that the two sides were once almost at war," he said in the address.
Zhang agreed with him that such a meeting would have been impossible earlier and called for "a little more imagination" regarding cross-Strait relations.
"We meet under great attention and expectations and bear great responsibilities," noted the mainland's Taiwan affairs chief.
He said he believed the two sides are heading in a straightforward direction and would not take long to fulfill their purposes.
