Hajimete no Happy Birthday! (初めてのハッピーバースディ!; Our First Happy Birthday!) is the first major label single released by Country Musume, as well as their fifth single overall, and the first single as Country Musume ni Ishikawa Rika. It was released on April 18, 2001. The single reached #4 on the Oricon charts and charted for six weeks, selling 142,340 copies. This is Country Musume's first single to appear on the Oricon charts, and their highest selling single ever.