A hanger running tool includes a hanger-contacting segment configured to move radially to engage a corresponding groove formed in a hanger to couple the hanger running tool to the hanger. The tool also includes a piston assembly comprising a first piston configured to couple to a seal assembly. The hanger running tool is configured to run the hanger and the seal assembly simultaneously into a wellhead, and actuation of the first piston is configured to energize the seal assembly to seal an annular space between the hanger and the wellhead.