Still under discussion
Engine restrictions are the most controversial of all the changes because many of the car manufacturers in F1 do not want there to be any.
As of today, the only rule on this is a restriction of one engine per race weekend from the start of the 2004 season.
Beyond that, there has been no agreement, although the FIA has suggested limiting teams to six engines for a season.
There is also a drive to force manufacturers to supply engines to a second team.
This is likely to be introduced after Mercedes, previously the most vociferous opponent, said it would be happy to agree.
To ease teams' financial problems, this may be extended to allow smaller teams to buy other parts - like chassis and gearboxes - off bigger ones.
The changes to the format of race weekends announced in October 2002 stay in place.
That means the following: