Resulting from the 26th Annual Larval Fish Conference of the Early Life History Section of the American Fisheries Society, in Bergen, Norway, this book presents current thought that reflects upon the following questions: when and in what capacity do developing organs or organ systems come on line, and more importantly, are these organs and their functions specializations unique to embryos and larvae or are they simply rudimentary functional anlage of the adult form? Understanding how larval fish function, how they acquire energy to grow, and how they expend energy to survive is basic to any endeavor in either mariculture or aquaculture.