Genetically-attenuated malaria parasites lacking essential genes are used as potent malaria vaccine candidates. CRISPR/Cas9-based gene editing is now a preferred method to create these parasites. However, these parasites must still be viable when administered as a vaccine, but completely arrested in the recipient. Therefore, precise, temporal expression of Cas9 is critical. To accomplish this, we have used a GFP reporter system to characterize the expression patterns of Plasmodium yoelii stage-specific promoters for expression of Cas9.