Simultaneous measurements have been recorded of the force, displacement and acoustic emission (AE) during the loading and unloading of a spherical indentor on to a silicon and a physical-vapour deposited 2.7 mu m thick TiN film on silicon. The AE signals were able to detect the formation of small cracks, such as Hertzian cracks, lateral cracks in silicon and to detect the onset of film cracking during loading and film delamination during unloading in TiN film. The measure data were also compared with SEM cross-section observations of the indented region. Excellent correlation between AE, force-displacement and SEM observation was found.