Integrated circuits in silicon technologies have been increasingly used for detecting and generating terahertz signals. Despite the limitations related to the devices speed and cutoff frequencies, circuit design techniques have been implemented to integrate terahertz systems well beyond those limitations. Imaging is one of the most targeted applications to demonstrate those systems. The large available bandwidth from 0.3-3THz combined with on-chip multi-element integration is enabling more application. Many challenges are still to be addressed, starting from the sources total radiated power, the tuning range, and the their coherence. The detectors are also in need of improved sensitivity, and tuning range. This presentation will focus on the design challenges of generating terahertz signals, and detecting them in silicon technology well beyond silicon device limitations. It will cover the recent circuit realization in CMOS technology and novel generation and detection techniques for enhanced terahertz imaging techniques.