This protocol is for purification of Cas9::NLSSV40::His6 from:Paix A, Folkmann A, Rasoloson D, and Seydoux G (2015) High Efficiency, Homology-Directed Genome Editing in Caenorhabditis elegans Using CRISPR/Cas9 Ribonucleoprotein Complexes. Geneticsgenetics.115.179382; Early online July 17, 2015. doi:10.1534/genetics.115.179382Please see the full manuscript for detail.