The new English Premier League (EPL) will feature two, as yet unnamed, overseas teams, in addition to England's 18 first-class counties, playing in two divisions of 10.
The existing Pro-40 competition, a 40 overs per side event, will end in 2009 and be replaced in 2010 by a Twenty20 League which will incorporate all 18 counties. This competition will be played primarily on Friday nights in July and August.
Plans were agreed at a board meeting on Tuesday.
An ECB statement added the Twenty20 League would be the qualifying tournament for the multi-million dollar Champions League, the inaugural edition of which takes place later this year and features the world's leading domestic Twenty20 sides.
The board's announcement put paid to the proposal put forward by MCC chief executive Keith Bradshaw and Surrey chairman David Stewart which envisaged a nine-team tournament similar to the lucrative Indian Premier League.
However, the ECB said the EPL would incorporate "elements" of the duo's plans, which did feature Friday night matches.
The board also agreed the 2010 season would, as happens at present, include a 50 over competition and aimed at a schedule which allowed for 16 County Championship matches to be played in a two division structure.
The EPL will be staged in June with the Twenty20 League being played in July, August and September.
ECB chairman Giles Clarke said: "I am delighted the board unanimously supported these creative proposals... we have already received enormous broadcast and sponsor interest from around the world which was reported to the board by the chief executive, David Collier."
Stewart added: "These are extremely exciting and satisfying proposals for the future of domestic cricket in England and Wales. They incorporate some excellent ideas and Keith Bradshaw and I were delighted to be able to submit our ideas as part of the decision making process."
The ECB's statement added Collier would be having further talks with parties identified by Bradshaw and Stewart as being interested in the EPL.