A map of all NCAA Division I basketball teams.

There are 347 schools in 32 Division I basketball conferences. Each conference, except for the newly formed Great West Conference, receives an automatic bid to the NCAA Men's Division I Basketball Championship. The conferences are as follows:

There are also 6 independent Division I schools without conference affiliation, for the 2009-10 season.

Division II

A map of all NCAA Division II basketball teams.

There are 22 Division II basketball conferences. The conferences are as follows:

There are also 18 independent Division II schools without conference affiliation, for the 2009-10 season.

Relationship to professional basketball

In past decades, the NBA held to tradition and drafted players who had graduated from college. This was a mutually beneficial relationship for the NBA and colleges—the colleges held onto players who would otherwise go professional, and the NBA did not have to fund a minor league. As the college game became commercialized, though, it became increasingly difficult for "student athletes" to be students. Specifically, a growing number of poor, under-educated, highly talented teenage basketball players found the system exploitative—they brought in funds to schools where they learned little and played without income.

The American Basketball Association began to employ players whose college classes had not yet graduated. After a season of junior college, a season at the University of Detroit, and an Olympic gold medal, Spencer Haywood played the 1969-70 season with the ABA's Denver Rockets. He signed with the NBA's Seattle SuperSonics in 1970, before his college class graduation, defying NBA rules. Haywood pleaded that, as his family's sole wage earner, he should be allowed to earn a living in the NBA or else his family would face destitution. The ensuing legal battle went to the U.S. Supreme Court which ruled in 1971 that the NBA does not have the same antitrust exemption enjoyed by Major League Baseball. Thereafter, collegiate players demonstrating economic hardship were allowed early entry into the NBA Draft. The hardship requirement was eliminated in 1976.

In 1974, Moses Malone joined the Utah Stars of the American Basketball Association (which became part of the NBA after the ABA-NBA merger in 1976) straight out of high school and went on to a Hall of Fame career. The past 30 years have seen a remarkable change in the college game. The best international players routinely skip college entirely, many American stars skip college (Shawn Kemp, Kevin Garnett, Kobe Bryant, Tracy McGrady, Dwight Howard, Amar'e Stoudemire and LeBron James) or only play one year (Carmelo Anthony, Chris Bosh, Kevin Durant, Greg Oden) and only a dozen or so college graduates are now among the 60 players selected in the annual NBA Draft. Fewer high schoolers will progress directly to the NBA without at least one year of college basketball beginning in 2006; citing maturity concerns after several incidents involving young players, the labor agreement between players and owners now specifies that players must turn 19 years of age during the calendar year of the draft to be eligible. Additionally, U.S. players must be at least one year removed from their high school graduation.

The pervasiveness of college basketball throughout the nation, the large population of graduates from "major conference" universities, and the NCAA's marketing of "March Madness" (officially the NCAA Men's Division I Basketball Championship), have kept the college game alive and well. Some commentators have argued that the higher turnover of players has increased the importance of good coaches. Many teams have been highly successful, for instance, by emphasizing personality in their recruiting efforts, with the goal of creating a cohesive group that, while lacking stars, plays together for all 4 years and thus develops a higher level of sophistication than less stable teams could achieve.