During the last ten years, our understanding of early child development, from conception through to 5, has greatly increased. This includes our understanding of neuro science and brain development, the ability to modify fetal development in the womb, and the move away from the traditional debate of nature vs. nurture to nature via nurture. It is vitally important that childcare social workers are fully aware of these issues if we are to intervene successfully to support children in need and children that need protecting. This book introduces the new science while affirming many of the older theories. By linking theories of child development with the law, policy, and guidelines, it provides students with a source that will enhance their learning, but also has meaning in day-to-day practice.