Microinjection has a long and distinguished history in Xenopus and has been used 
to introduce a surprisingly diverse array of agents into embryos by both intra- 
and intercellular means. In addition to nuclei, investigators have variously 
injected peptides, antibodies, biologically active chemicals, lineage markers, 
mRNA, DNA, morpholinos, and enzymes. While enumerating many of the different 
microinjection approaches that can be taken, we will focus upon the mechanical 
operations and options available to introduce mRNA, DNA, and morpholinos 
intracellularly into early stage embryos for the study of neurogenesis.