Substantial progress in pisciculture has been made in the last two decades, but many unidentified parameters that can still affect juvenile quality and, therefore, limit the costeffectiveness of the production represent an industrial bottleneck. The most critical phase of the whole production cycle is probably the larval period. To control this phase of the production cycle, it is essential to decipher the ontogenetic mechanisms and underlying regulations governing the harmonious development of the larvae in order to understand the disruptions induced by environmental/nutritional factors. It is now well admitted that the regulation of the developmental processes involves the control of the expression of genes whose products influence the biological functions related to ontogenetic pathways. The recent development of the genomic resources in European sea bass allows the investigation of a large panel of genes involved in different biological processes and notably to study simultaneously the expression of several thousands of genes. This chapter reviews the recent data related to larval development obtained through transcriptomic approach in sea bass and provides an overview of the effects of dietary vitamins on the expression of several key genes acting on the skeletogenesis processes. © 2012 John Wiley & Sons, Inc.