The zebrafish, originally an object of study as an inexpensive and prolific vertebrate embryological model with a plethora of genetic tricks, has over the past decade moved to large-scale chemical mutagenesis and recently came of age as a high throughput transgenic model with a sequenced genome nearing completion. Insertional mutagenesis, gene trapping and enhancer detection are all contributing to the increasing speed with which research in this biomedical model is progressing. We review here some of the recent developments in the emerging field of zebrafish developmental genomics and transgenesis. Developmental Dynamics 234:255–268, 2005. © 2005 Wiley-Liss, Inc.