Here's a brief rundown of how the calendar shakes out leading up to the 2012 NBA Draft.
April 11-14th - Portsmouth Invitational
A pre-Draft camp for seniors, though top prospects rarely attend
April 29th - Early-entry deadline
College players need to enter the Draft by the 29th, but can withdraw by May 8th
May 8th - College players need to withdraw
College players that declared early need to withdraw or be locked into the Draft
Mid/End of May - NBA Draft Lottery
Televised during the NBA Playoffs
End of May - NBA Draft Combine
Held in Chciago, for the top NBA Draft prospects
Early June - International Combine
Held in Europe, a camp for top international prospects
June 18th - International players need to withdraw
International players that declared early need to withdraw by the 18th or be locked into the Draft.
June 28th - 2012 NBA Draft
Held at the Prudential Center in Newark, NJ. The public can buy tickets to attend the Draft.