Type I Neurofibromatosis (NF1) is a common autosomal dominant genetic disorder caused by loss of function mutations in the NF1 gene. Drosophila and murine models of NF1 have provided significant insight into disease pathogenesis and NF1 biology; however important questions remain that cannot be efficiently addressed in these systems. In this dissertation, I describe the generation of a novel zebrafish model of NF1. I identify the zebrafish genes orthologous to human NF1 and characterize their expression patterns during development. Through a series of transient loss-of-function analyses, I demonstrate novel roles for neurofibromin in vascular development and in in vivo migration of oligodendrocyte progenitor cells. I go on to develop stable lines of zebrafish harboring mutations in the human NF1 orthologues by targeted mutagenesis using zinc finger nucleases and TILLING. I present preliminary data from these mutant zebrafish lines confirming transient knockdown phenotypes and describe our observation of new and potentially clinically relevant NF1-associated phenotypes that have not been successfully modeled in other systems. These reagents will serve as a powerful platform to investigate important questions about NF1 pathophysiology.