Once upon a time, nothing was more exciting than finding cures for infectious diseases. Sinclair Lewis's 1925 novel Arrowsmith, about a medical doctor who after many hard lessons decides to dedicate his life to basic research, inspired American kids who grew up to become the leading scientists of their generation.

But here's the thing about fashion: in the 1930s and 40s many of those whom Arrowsmith had inspired, including Ernest Lawrence's associates Glenn Seaborg, the famed element hunter, and Robert Wilson, the creator of Fermilab, chose to study nuclear science, not medicine. Times had changed.

Today's buzzword is nanoscience, which promises discoveries in many disciplines. Berkeley Lab's Molecular Foundry, one of the Department of Energy's five nanoscale science research centers, saw its official opening on March 24; already underway were programs in organic, inorganic, and biological nanostructures, and imaging, fabrication, and theory. Fashionable science, but is it really a new thing?

No and yes. The application of new techniques to old questions allows not just practical fixes to old problems but whole new kinds of questions, as Berkeley Lab's own history demonstrates. At first Lawrence's laboratory emphasized atoms, atomic nuclei, subatomic particles, and the machines to study them, but almost from the beginning there was an equal emphasis on the medical applications of radiation. Nuclear science itself generated unexpected fields of inquiry: the discovery of radioactive carbon-14 found applications from archaeology to photosynthesis.

Today the scientific descendants of those once-fashionable beginnings — cosmology, genomics, materials sciences, earth sciences, new sources of energy and more efficient ways to use it — are like streams and rivers fed by mountain springs. Satisfying the thirst for knowledge means understanding its sources as much as rushing toward a goal. Even as today's fashions fade, the future is a sea that will change them into something rich and strange.

This issue of Science@Berkeley Lab celebrates fashionable science, such as measurements that will make new electronic gadgets possible, as well as more basic science, like investigations into the nuclear processes that created the elements we're made of, plus science at its simplest and most essential — including how to cook with less wood, in the refugee camps of Darfur.

— Paul Preuss, Editor, Science@Berkeley Lab