Spin‐polarized electron energy‐loss spectroscopy has been used to investigate the probing depth of low energy (∼30 eV) electrons at metal surfaces and to study the growth and morphology of monolayer‐level metal films. Studies of the Cu(100)/Mo system show that the probing depth in molybdenum is small, ∼1 monolayer, and that molybdenum grows layer‐by‐layer on Cu(100). Data for the Cu(100)/Fe system are also reported that suggest that iron deposition on a room‐temperature Cu(100) substrate does not initially result in simple layer‐by‐layer growth.