This text, the result of three decades of research and instruction, provides a guide to the developing prenatal rat brain. The use of advanced computer graphics alongside more than 265 plates that reconstruct brain slices revolutionizes the study of the highly vulnerable prenatal brain, and clarifies the understanding of its malfunctions, deficits and abnormalities. A detailed and logical classification of the germinal matrix at early stages is provided, as is a double systemmatic and synonym index for cross-referencing.