June 15, 2003 (Sunday)
- The German Green Party backs Chancellor Gerhard Schröder's Agenda 2010 with more than 90% of all votes at an extraordinary party convention.
- The San Antonio Spurs become NBA basketball champions by defeating the New Jersey Nets in game six of the 2003 NBA Finals, 88–77. It is the Spurs second franchise title.
- American and Canadian researchers publish a paper that uses gene linkage techniques to identify a mutation in the GRK3 gene as a possible cause of up to 10% of cases of bipolar disorder, one of the major mental illnesses.