This article covers the most important design techniques for Gaussian pulse generation, an essential function for many ultrawideband (UWB) impulse radar systems. Gaussian pulse-shaping networks of step recovery diodes (SRD), avalanche transistors (AT), tunnel diodes (TD), nonlinear transmission lines (NLTL), and microstrip transmission lines (TL) are reviewed. Comprehensive discission includes performance comparisons that highlight pulse amplitude, pulse width, ringing percent and applications for each of these approaches. Research problems remain such as the generation of high voltage picosecond impulses and high voltage impulses with low-ringing. Lower voltage nanosecond Gaussian impulse generation is also problematic. Gaussian pulse generation has the potential for new medical applications by improving image contrast and resolution.