Nightmares are defined as disturbing mental experiences that generally occur during REM sleep and often result in awakening. Whereas the number of publications addressing nightmare frequency and psychopathology, nightmare etiology and treatment is increasing rapidly in the last few years, nightmare content has been studied very rarely in a systematic way, especially in adults. The present study investigated nightmare frequency and the frequency of various nightmare topics in a representative German sample. The five most common themes were falling, being chased, paralyzed, being late, and the deaths of close persons. Even though several effects can be explained by the continuity hypothesis of dreaming, further research is needed to investigate the possible metaphoric relationship between nightmare topics like falling or being chased and waking-life stressors.