Microelectronic packages continue to undergo significant changes to keep pace with the demands of high- performance silicon. From the traditional role of space transformation and mechanical protection, packages have evolved to be a means to cost-effectively manage the increasing demands of power delivery, signal distribution, and heat removal. In the last decade or so, increasing frequency and power levels coupled with lower product costs have been driving new package technologies. Some examples of this are the migration from wirebond to flip chip interconnect and ceramic to organic package substrates. Recently, architectural changes like the introduction of multicore processors, material changes such as the low-K dielectrics on the silicon, and lead-free second-level interconnects have introduced a new set of challenges that require innovative package technology solutions. As we look forward, increased levels of current, increased power density, and high-bandwidth signaling are expected to create challenges in all disciplines within the package field. In addition to these technical challenges, market forces such as declining computer prices, increased user experience through miniaturized devices, wireless connectivity, and longer battery life would make these challenges even more complex. In this paper we provide an overview of trends and challenges in the areas of power delivery, signal transfer, thermal management, miniaturization, and wireless package technologies. We also examine some of the potential solutions that are being developed to meet these challenges.