Our research program is focused on the development and application of femtosecond laser surgery and optical neurophysiology to the study of the nervous system of the nematode worm C. elegans. Using tightly focused pulses from an ultrafast laser, we can ablate regions of biological tissue with submicron precision, making it possible to snip individual nerve fibers within an intact worm (Fig 1). This enables in vivo study of neural regeneration and dissection of neurocircuitry at a new level of resolution. A small transparent body, simple stereotyped nervous system and powerful genetic tools combined to make C. elegans an ideal model organism for this work. Femtosecond laser technology applied to this versatile and tractable system allows us to tackle fundamental questions in neural regeneration and function.