This work reports the current status of the project Penetrating radar systems for urban operations. In particular is in this report accounted for the activities within the work of detecting human activity "around the corner", i.e., the ability with a radar system in an urban environment to utilize multiple scattering and diffraction in order to be able to detect objects which are not in the line-of-sight of the radar. This new way of using a radar is developed by FOI. The report first gives an overview of earlier activities, largely performed within the strategic research project Radar for detection of human activity around the corner. Next, more recent activities are described in somewhat more detail. This latter part consists mainly of two parts. First a more practical part, focused on exploiting real measurement data in order to detect and position obscured moving objects and then a more theoretical study investigating the possibility to position targets by using estimated and/or calculated impulse response. The measurements are collected via a simple antenna setup, which means more advanced signal processing cannot used. We demonstrate that it is nevertheless possible to position a moving target by using multiple scattering. Especially, it is the multiple reflections that are used, while the contribution from the diffraction is harder to judge. In the theoretical study it is shown, firstly, how an imagined array antenna extending in the horizontal plane can give a two-dimensional positioning of a synthetic target. Secondly, it is shown that if the array antenna in addition has an extension in the vertical dimension, one also get a resolution in that direction. In both cases, one reaches fairly positive conclusions, but it is also clear that there are many difficulties to address. The methods accounted for here, including the modeling of the scenario, can be developed in many different directions. For that reason should the more technical questions at issue be supplemented with an increased understanding of the requirements on these kinds of systems.