In the past three decades, cognitive neuroscience has become an important force in humanity's efforts to understand itself. So great and so relevant are its potential contributions that Eric Kandel was moved to say: “Cognitive neuroscience — with its concern about perception, action, memory, language and selective attention — will increasingly come to represent the central focus of all neurosciences in the 21st century.”

To celebrate this diverse and exciting field, we bring you this special focus issue on cognitive neuroscience. Our authors cover issues that include recognition, awareness, decision making and memory; and draw on all of the techniques of modern cognitive neuroscience, including functional imaging, modelling, neuropsychology, psychophysics and electrophysiology. As an illustration of the new directions being taken by cognitive neuroscientists, just take a look at Ralph Adolphs's review of the neurobiology of social behaviour. The new field of 'social cognitive neuroscience' promises to reveal the neural underpinnings of our social interactions, which are so important to our lives and yet so little understood.

Cognitive neuroscience is by its very nature cross-disciplinary, and as such reflects the increasing trend in the neurosciences as a whole towards collaboration and cross-fertilization of ideas. We hope that this issue will appeal not just to the cognitive neuroscientists among our readers, but also to neuroscientists of other kinds, and that it will encourage discourse between cognitive neuroscientists and their colleagues in other specialities. To ensure that everybody has an opportunity to enjoy this focus issue, its contents, along with a selected library of cognitive neuroscience content from past issues of Nature Reviews Neuroscience, will be available free online during March 2003.