1. Needle Microinjection: A Brief History.- 2. Microinjection of Macromolecules into Mammalian Cells in Culture.- 3. The Use of Plasmid Microinjection to Study Specific Cell Cycle Phase Transitions.- 4. Combining Microinjection with Microanalytical Methods to Investigate Regulation of Metabolic Pathways.- 5. Import of Stably Folded Proteins into Peroxisomes.- 6. Study of the Function of Microtubule Proteins.- 7. Cytoskeleton Regulation by Rho Proteins.- 8. Cytoskeletal Regulation by Rho-p21 Associated Kinases: Analysis of ROK and PAK Function by Plasmid Microinjection.- 9. Use of Microinjection to Study Apoptosis and its Prevention.- 10. Role of the InsP3 Receptor in Intracellular Ca2+ Release and Ca2+ Entry.- 11. Microinjection of Xenopus laevis Oocytes: A Model System.- 12. Xenopus laevis Oocytes as a Model for Studying the Activation of Intracellular Kinases.- 13. Signal Transduction in Xenopus laevis Oocytes by Ras Oncoproteins and Lipid Metabolites.- 14. The Multiple Roles of Mos During Meiosis.- 15. Use of the Xenopus Oocyte System to Study RNA Transport.- 16. Functional Expression of G Protein-Coupled Receptors in Xenopus laevis Oocytes.- 17. Expression of Glucose Transporters in Xenopus laevis Oocytes: Applications for the Study of Membrane Transporter Function and Regulation.- 18. DNA Injection into Xenopus laevis Embryos as a Tool to Study Spatial Gene Activity.- 19. Transformation of Nematodes by Microinjection.- Guide to Solutions.- Guide to Protocols.- Troubleshooting Guide.