This paper addresses the optimization of front-end design in position sensing, imaging and high-resolution energy dispersive analysis with room temperature semiconductor detectors. The focus will be on monolithic solutions able to meet the requirements of high functional density set by multielectrode, finely segmented detectors. Noise will be an issue of dominant importance in all the analysis developed here. It will be shown that the front-end optimization process requires two subsequent steps. One is the choice of the technology. The most advanced CMOS processes featuring a short channel and a very thin gate oxide will be evaluated along with technologies that feature a Junction Field-Effect Transistor (JFET) as an input device. Once the technology and therefore the nature of the preamplifier input element is chosen, the second step is directed to optimizing the design of the input stage. This process requires that some criteria that have been used to this effect ! in the past and were restricted to the sole input element be revisited. It will be shown, indeed, in this paper that the optimization process, especially as far as noise is concerned, must take into account the fact that the preamplifier input stage is customarily a cascode and therefore the noise in the common gate element affects the optimization of geometry and working point of the input device. This consideration will be applied to the choice of the optimum aspect ratio and working point for either a CMOS or a JFET employed as front-end devices. Attention will be devoted in particular to the choice of the channel length in a CMOS design, a point that has acquired particular importance with the advent of submicron CMOS technologies. The discussion of practical design examples based on the previous considerations concludes the paper.