Abstract: Filters are some of the few remaining RF/microwave components that are fabricated off chip. As a result, filters account for a significant portion of wireless device cost and size. Therefore, integration of filters is highly desirable. In the first part of this work presents the analysis, modeling and measurements of a novel on-chip filter using a monolithic transformer that can be integrated on silicon substrate. A comprehensive review of the performance of passive inductors and transformers is presented, along with a new approach to design filters using transformers. An experimental version is fabricated using the Motorola 0.18 micron process. The filter is designed using Z-shaped multilayer transformers to enhance figures of merit. Measurement results show significant improvement in the performance over the original, inductor, implementation. The size and Q advantages of the new topology can be useful in cost sensitive consumer products. A US patent has been allowed based on this work. In the second part of this work, integration of filters at the package level is investigated. The main focus of this work is the miniaturization of high Q distributed filters using embedded high k substrates that can be supported by LTCC technology. Such a technology is difficult to implement at chip-level. Distributed hair-pin filters are initially investigated. Because of its small size (half of the size of coupled line filters) and design simplicity, X-band is probably the most common application of conventional hairpin, but even with 2:1 size reduction, the size is still large for integrated wireless applications. The proposed filter utilizes a W-shape resonator with improved feed probes that enhance the filter selectivity. Using LTCC technology, the new filter structure is formed between a high k material followed by a low k material. The high k material minimizes the physical size of the distributed filters, while outside the high k materials, fields are evanescent and little of the field reaches the ground planes, which reduces the conductor loss of the filter. Simulations and measurements results of the new filter show improved filter characteristics while reducing the size to half of the conventional hair-pin.