Considerable progress has been made in integrating multi-Gb/s functions into silicon chips for data- and telecommunication applications. This paper reviews the key requirements for implementing such functions in monolithic form and describes their implementation in the IBM SiGe BiCMOS technology. Aspects focused on are the integration of 10ߝ13-Gb/s serializer/deserializer chips with subpicosecond jitter performance, the realization of 40ߝ56-Gb/s multiplexer/demultiplexer functions and clock-and-data-recovery/clock-multiplier units, and, finally, the implementation of some analog front-end building blocks such as limiting amplifiers and electro-absorption modulator drivers. Highlighted in this paper are the key challenges in mixed-signal and analog integrated circuit design at such ultrahigh data rates, and the solutions which leverage high-speed and microwave design and broadband SiGe technologies.