Dynamic adhesion and fracture behaviors of surfaces and films are studied in the Surface Forces Apparatus using the ‘FECO' optical interference technique which allows one to observe surface shape changes on micro and nano scales. In particular, transitional behaviors are investigated when surfaces or films change from liquid-like to solid-like states. We will address the micromechanical properties of liquid and solid surfaces and types of instabilities observed during their approach, contact and detachment, and discuss common situations where similar effects likely occur.