In this paper we review the work done in our laboratory on femtosecond laser dissection within single cells and living organisms. Precise dissection of biological material with ultrashort laser pulses requires a clear understanding of the pulse-energy dependence of the onset and extent of plasma-mediated ablation (i.e., the removal of material). We carried out a systematic study of the energy dependence of the plasma-mediated ablation of fluorescently-labeled subcellular structures in the cytoskeleton and in nuclei of fixed endothelial cells using femtosecond, near- infrared laser pulses focused through a high- numerical aperture objective lens (1.4 NA). We performed laser nanosurgery in live cells, where we ablated a single mitochondrion and severed cytoskeletal filaments without compromising the cell membrane or the cells viability. We also cut dendrites in living C. elegans without affecting the neighboring neurons. This nanoprocessing technique enables non-invasive manipulation of the structural machinery of cells and tissues down to several-hundred- nanometer resolution.