Radio Frequency MicroElectroMechanical System (RF MEMS) switches are Very promising MEMS devices ready to commercialize for wireless network, mobile phone, radar, instrumentation, and sensor applications. In this report, we will first review some of the MEMS devices fabricated at IMETU, the enabling technologies of making these devices, and their potentially industrial applications. And then,we will focus on RF MEMS switches and Bridge Type Resonators. Of these two kinds of MEMS devices, our RF MEMS switches show an eYCellent RF performance and reliability with a lifetime of 100 million switching cycles, and our Bridge Type Resonators as special MEMS switches have dimensions scale down to nano-size with eYCellent prisical and mechanical properties which will revolutionize the sensor technology. Finally, we will discuss the design and fabrication of phase shifter as a key element for MEMS switches, and several different RF MEMS switch packaging strategies for the purpose of commercialization.