Nasıl Delirdim? (How Did I Go Mad?) is the fifth studio album by Turkish singer Hande Yener. It was released on 15 May 2007 by Erol Köse Production. The album contains elements of electronic, pop, house, downtempo, dance and club music, and was the singer's first studio album since the 2006 release of Apayrı. Nine of the album's songs were written and composed by Boaz Aldujeli, making him the songwriter whose name appears the most in the album. Hande Yener served as the album's producer.