Since Nuclear Medicine diagnostic applications are growing fast, room temperature semiconductor detectors such CdTe and CdZnTe either in the form of single detectors or as segmented monolithic detectors have been investigated aiming to replace the NaI scintillator. These detectors have inherently better energy resolution that scintillators coupled to photodiodes or photomultiplier tubes leading to compact imaging systems with higher spatial resolution and enhanced contrast. Advantages and disadvantages of CdTe and CdZnTe detectors in imaging systems are discussed and efforts to develop semiconductor-based planar and tomographic cameras as well as nuclear probes are presented.