The authors discuss several important circuits for fiber-optic transmission, implemented in an advanced silicon bipolar integrated circuit technology. Specifically, the authors discuss the design considerations and measured performance of a 2:1 multiplexer, front end receiver, limiting amplifier, and decision circuit IC. Also discussed are three hybrid circuit modules: a 2:1 multiplexer, 1:2 demultiplexer, and parallel processing decision circuit. These ICs and hybrid circuit modules operate at multi-Gb/s data rates. The performance of these ICs indicates that advanced silicon bipolar integrated circuits with their high speed, functionality and low cost potential could play an important role in alleviating the electronic bottleneck in future multigigabit optical communication systems.>