See PxrDisplace for how to add scalar and vector displacement as well as displacement layers.
Add a PxrDisplace VOP to your RIS Network and connect to the PxrMaterialBuilder's output_collect node. Wire your displacement map such as creating a PxrTexture VOP or PxrPtexture VOP for texture or ptex respectively. We can wire a shading network also. We recommend vector-based displacement, especially when layering.
Wire your PxrDisplace VOP to the shader input of the output_collect node.
Displacement settings are found on the RenderMan tab > Primvars > Shading > Displacement on the geometry OBJ being displaced.
Trace displacements is on by default.
Set a displacement bound to render displacement, a setting of 0 turns off displacement on the object.