A mechanical-loading stage operating inside a scanning electron microscopy (SEM) was used to realize the sliding between nested shells of multiwalled carbon nanotubes (MWCNTs). A stick-slip motion and a smooth pullout motion were observed for the two separate MWCNTs studied. A model that includes the shear interaction, the "capillary" effect, and the edge effect, was used to explain the observed sliding between nested shells. The shear strength between shells was determined and the surface energy of the MWCNT shell estimated.