The processes of cell migration and invasion are integral to embryonic development and the functioning of adult organisms. Deregulation of these processes contributes to numerous diseases. Ras GTPases and in particular members of the Rho subfamily of GTPases play critical roles in cell migration and invasion. Here, we provide a collection of protocols to assay these functions. We describe two cell migration assays. The monolayer wound healing assay is very easy to implement, whereas the microliter-scale migration assay allows examination of cell behavior on defined extracellular matrices. We also describe two methods that allow the quantification of tumor cell invasion, a versatile transwell Matrigel invasion assay and an organotypic assay that examines the invasion of glioma cells through a rat brain slice.