Today's electronic products are required to be increasingly small, fast, low power, light weight and feature-rich. These requirements have been converted to the electronic domain as smaller IC package with higher number of I/O. To accommodate higher I/O in a shrinking package size, the pin pitch needs to be reduced tremendously. To align with the drastic growth of package technology, PCB technology needs to advance in the area of design, fabrication and assembly to support the fine pitch package interconnection to PCB. This paper attempts to elaborate the challenges in supporting high density PCB with 0.40 mm pitch BGA from design, fabrication and assembly perspective, as well as discussing the current workarounds and solutions to the challenges and difficulties faced with today PCB technology.