Memory serves critical functions in our daily lives, but it is also vulnerable to forgetting and distortion. Two decades ago, Dr. Daniel Schacter proposed that memory errors could be classified into seven basic categories or “sins”: transience, absent-mindedness, blocking, misattribution, suggestibility, bias, and persistence. Although each of the seven sins can cause significant problems in everyday life, they also provide important insights into the adaptive nature of human memory. In this talk, he will summarize some important developments during the past two decades that have increased our understanding of the nature, consequences, and adaptive functions of the memory sins.