Combining metal-like conductivity, termination-tunable work function, and excellent thermal spreading, MXene enables a new class of contact for next-generation electronics. On 2D semiconductors such as MoS2, low-temperature, solution-processed MXene contacts reduce work-function mismatch, supporting high-yield transistor arrays for integrated microelectronic circuits. MXene can form a damage-free van der Waals gate contact to AlGaN/GaN HEMTs, suppressing leakage and enabling high-field operation with high breakdown voltage in wide-bandgap electronics. Extending the tunable interface chemistry, MXene contact also applies to p-type semiconductors, such as MoTe2 and Te nanowires, where conformal, low-temperature contacts preserve intrinsic anisotropy while delivering efficient carrier injection. Across these platforms, we connect interface chemistry to device physics and packaging, turning contacts from bottlenecks into accelerators and delivering reliable, energy-efficient electronics.