Given limited opportunities for space flights, ground based experiments represent an important means for providing initial data regarding the effects of microgravity to guide future work in space. Currently there are four commonly used methods to simulate microgravity for periods sufficient to investigate developmental processes: the rotating wall vessel (RWV), 2- and 3-D clinostats and the random positioning machine (RPM). To date most research simulating microgravity has been performed on cell cultures and suggests that simulated microgravity induces changes in the rates of cellular proliferation and differentiation. In this study we aim to test whether these effects were present in whole organisms. Our laboratory is currently developing protocols for the use of zebrafish embryos in the 3-D clinostat, as well as in the 2-D clinostat and RPM to test whether this trend is observed in other modalities of simulated microgravity (SMG). Our results will allow the first comparison of the effects of the different methods of simulating microgravity on whole-embryo development. These findings will provide insights into how zebrafish may develop in space, permitting better formulation of experiments to test the mechanisms by which microgravity affects ontogeny in this model organism.