This chapter discusses the case of a 46-year-old female with a 5-year history of distressing, unpleasant and bizarre dreams that occurred from a few times a week to once a month, depending on her stress level. It presents the clinical history, examination, diagnosis, follow-up, general remarks and the results of the procedures performed on the patient. Nocturnal polysomnography (PSG) was carried out, and the thyroid-stimulating hormone level in plasma was determined. The diagnosis was nightmare disorder with primary snoring. The relationship between daytime stress, anxiety and nightmares was emphasized. The treatment plan centered on addressing daily stress and anxiety. Recurrent nightmares are frequent in children (20-39%) and less frequent in adults (5-8%). Nightmares also occur in patients with psychiatric illnesses such as anxiety, depression and schizophrenia, as well as in individuals with poor coping mechanisms and creative tendencies.