Packaged MEMS devices for RF applications have been modelled, realized and tested. In particular, RF MEMS single ohmic series switches have been obtained on silicon high resistivity substrates and they have been integrated in alumina packages to get single-pole-double-thru (SPDT) and truetime-delay-line (TTDL) configurations. For this purpose, the individual switches have been considered as the building blocks of more complicated structures, and the alumina substrate has been properly tailored in order to get the best electrical performances considering all the technological steps necessary for the final