Multi-chip modules (MCMs) with high wiring density, controlled impedance interconnects and thermal management capability have been developed to address the problems posed by advances in electronic systems that make demands for higher speeds and complexity, highlighting recent advances in MCM-C technology. Developments in materials and processes which have led to increased interconnection density are reviewed for finer resolution thick film inks and high performance-low temperature dielectric tapes. Precision via generation by both laser and mechanical methods and enhanced screen printing technologies have provided feature resolution to the 50 mmm line/space level. MCM-C technology is compatible with thick film sensors and work is reviewed on environmental gas sensors, pressure and temperature sensors, and the development of novel materials in this area.