The book presents the design and fabrication of RF MEMS switches and switch circuits. It presents RF MEMS capacitive switches and MEMS tunable filter first ever to be produced in Norway. Modeling and design of high speed switches and high capacitance ratio switches are presented. Design and simulation of tunable low pass and bandpass filters are also described. A model for pull down voltage of a non-uniform bridge and cantilever is also highlighted. The fabrication of the capacitive switches and MEMS tunable filters, conducted in the SINTEF MiNa lab is described in details. Measurements of pull down voltage and characterization of RF performance for the switches and filters (low pass and band pass) are also presented.