Mine detection using active radar systems is the subject of a number of research programs both in the US and in Europe. This paper considers the environmental and operational drivers that influence the design of such radar systems. The prime system architectures are time domain and frequency domain configurations and each has its merits. The majority of the ground probing radars used at present are time-domain ultra- wideband radars and their characteristics are well established, while a smaller proportion of radars operate in the frequency domain, using FMCW, stepped frequency or noise modulation. The complexity and cost of the latter type of radar is at present greater than the time-domain radars but theoretically offers a better dynamic range. This paper considers the characteristics of these generic radar systems and the factors that need to be considered in system design. The performance of the antenna significantly affects the overall system and the paper qualitatively discusses this aspect. For GPR, an important technical challenge is associated with achieving a well-defined antenna footprint to maximize the signal to clutter ratio and consideration will be given, in the paper, to time domain array antennas for mine detection. The results of studies carried out during EU funded programs will be reported in this paper. The radar image of the mine depends not only on its construction and on geometry but also on the local environment, hence prior assumptions about the radar spatial signature of the mine may be ill- founded.