While the concept of Angle-resolved XPS has been available since the early days of XPS, its use has always been limited both due to its demanding experimental overhead and the difficulties of data interpretation. The introduction of systems allowing recording several angles in parallel has greatly eliminated the experimental difficulties and pushed the development of more integrated software’s for data interpretation. Simultaneously, the advent of use of very thin film across many industries and especially for high-k dielectric in the microelectronics industry, the ability to accurately and quickly evaluate the true composition, including species location within a layer, has become more complicated, or even impossible. Specifically, a depth profile involving ion sputtering will cause a rearrangement of species by degrading the analytical results. Non sputtering techniques such as ERD or MEIS have achieved high quality, quantitative depth profile on very thin layers. However, ERD and MEIS are complex techniques from both an instrumental and theoretical point of view. This paper will present the possibilities of composition depth profiling for thin films (<5nm) by XPS without the need for sputtering. We will however emphasize the danger of blindly applying the technique through the use of several examples. The use of ARXPS is however not limited to depth profiling of ultra-thin layers. We will also include example of application in the field of organic chemistry, bio-sensors, etching and cleaning process development, where the additional qualitative information available through angle-resolved measurement significantly simplify the interpretation of the data.