A thin-film coating generally is a single or multiple layered thin film deposited on a component to extend its life and performance. As discussed in this paper the V(z) effect in line-focus acoustic microscopy is a very suitable technique for the quantitative nondestructive determination of thin-film elastic constants and the bond quality at interfaces. After a brief introduction to acoustic microscopy and a discussion of calibration for frequency dependence, the modeling of multilayered configurations is summarized. The modeling results are used in a measurement model for the V(z) effect which can be used to select a frequency range suitable for a particular configuration. In combination with measurements the model is subsequently employed to determine elastic constants and interface stiffnesses. Experimental results are presented for single, multilayered, isotropic and anisotropic films. The effect of imperfect interfaces on strength considierations is also discussed.