Although Xenopus oocytes are very hardy and robust for experimentation and offer unusually simple and inexpensive opportunities for the delivery of mRNA to the cytoplasm and DNA to the nucleus, they are underutilized as an experimental model. In "Xenopus Protocols: Cell Biology and Signal Transduction," hands-on researchers describe standard and cutting-edge techniques for using Xenopus oocytes and oocyte/egg extracts to reconstitute biological and cellular processes. These readily reproducible methods take advantage of the oocyte's impressive protein abundance (for example, 50-70 ng catalytic subunit of PKA per oocyte), its striking protein translation capacity (200-400 ng protein/oocyte per day), and its breathtaking possibilities for the assembly of infectious viral particles by single-cell injection of multiple RNAs. The authors focus on the versatility of frog oocytes and eggs.