SEMARK is a research project which has been carried on during the years 2004-2009 in two stages. Focus has been surveillance with multiple sensors against objects on ground. The work has been carried out along three paths: simulation, measurement campaigns to get calibration data and creation of a concept for ground surveillance with multiple sensors. In the second stage of the project, focus has been to study usage, coordination, management and control of the sensors. We have also studied how the support systems around the concept might look like as well as a possible development path. The basis for our concept is that no single sensor system alone, can fulfil all kinds of information requests during a ground surveillance operation, Together, working as a system, they can fulfil demanding requirements from the users. Our work has showed that our concept idea might lead to a powerful and flexible ground surveillance system. However, to gain full performance it requires considerable research and development work. But, already today, the defence forces can use results from our work to raise the capabilities using current systems.