Delayed Sleep Phase Disorder (DSPD) is a circadian rhythm sleep disorder where a person's sleep-wake cycle is significantly delayed. Individuals with DSPD typically find it difficult to fall asleep until late at night, often after midnight, and struggle to wake up in the morning. This misalignment can lead to insufficient sleep and daytime sleepiness. People with DSPD may experience challenges in daily life, such as difficulty attending work or school on time. Treatment options include light therapy, melatonin supplements, and behavioral strategies to help reset the sleep-wake cycle and improve overall sleep quality.