2008 Olympic Selection Procedures for United States (also known as USA) 
swimming[]
How do swimmers qualify for the United States (also known as USA) Olympic Team at the 2008 U.S. Olympic Team Trials Swimming?[]
There is an official document posted on http://www.usaswimming.org and available in the Media Center that outlines the official USOC qualifying procedure for athletes trying to make the 2008 U.S. Olympic Team.
The below is provided as an unofficial explanation written for the fan program by SPLASH editor, Jim Rusnak.
1. Athletes must qualify for and compete at the 2008 U.S. Olympic Team Trials - Swimming, held June 29-July 6, in Omaha, Neb. If you don't compete here, you cannot make the Olympic Team in the pool events. Open Water Trials are a separate affair and have already been contested.
2. Swimmers who finish in the top four of the 100- and 200-meter freestyle at Trials, along with the first-place finishers in all the other events are named to the team first.
3. A maximum of 26 men and 26 women can be named to the Olympic Team, so provided all the spots have not been filled by the top four finishers in the 100 and 200m free and the first-place finishers in all the rest of the events, the second place finishers in each of the other events will be added to the team in a priority order based on an integrated world ranking from 2007 and 2008.
4. If, after adding the second-place finishers from each of the other events there is still room on the team, the fifth- place finishers from the 100 and 200m free are added (using the same world ranking as listed in #3 above).
5. If, after adding the fifth-place finishers from the 100m and 200m free there is still room on the team, the sixth- place finishers from the 100m and 200m free are added. For your average spectator, that's really all there is to know (using the same world ranking as listed in #3 above). Of Note:
Since the Olympic Trials have taken on this format, the top six swimmers in the 100m and 200m free, along with the top two swimmers in each of the other events, have always made the U.S. Olympic Team.