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Dreaming has been a subject of huge fascination in psychology and neuroscience since the nineteenth century. However, despite recent advances, this phenomenon remains deeply enigmatic. Described as a modified state of consciousness occurring during sleep, characterized by vivid sensory, cognitive, and emotional experiences, it is widely accepted that dream reports are the reflection of memories of dream experiences. However, numerous methodological and theoretical pitfalls are still slowing down neuroscientists in their research on production and memorization of such experiences. During the last decade, numerous studies have described the beneficial effect of sleep on memory, bringing back the idea that memory consolidation processes could underpin dreaming. However, surprisingly, studies reveal that dream reports are rarely related to specific episodic memories, and neither content nor frequency seem to be clearly related to memory performance. Here, we review studies that focused on the relationship between dreams and memory, and address two main questions: (1) Can we define the type of memories that are replayed during dreams? (2) Do dreams play a role in consolidation and the reorganization of memory during sleep? We detail a model describing the assimilation of recent memories in global memory frameworks during sleep, in line with neuroscientific data from dream studies and knowledge from dreams reports. We finally emphasize the importance of dreamers' reports for the understanding of memory consolidation processes and their contribution to neuropsychology in normal aging and neurodegenerative diseases.