The ability to remember is perhaps the most significant and distinctive feature of our mental life. We are who we are largely because of what we have learned and what we remember. In turn, impairments in learning and memory can lead to disorders that range from the moderately inconvenient benign senescent forgetfulness associated with normal aging to the devastating memory losses associated with Alzheimer disease. Of the various, higher-cognitive abilities that human beings possess, such as reasoning and language, memory is the only one that can be studied effectively in simple experimental organisms that are accessible to genetic manipulation, such as snails, flies and mice. In these organisms, the effectiveness of genetic approaches in the study of memory has improved significantly in the past five years. Below we review these advances.