The following features of Analysis and Design of Quadrature Oscillators make it different from the existing literature on electronic oscillators: (1) focus on quadrature oscillators with accurate quadrature and low phase-noise, required by modern communication systems; (2) a detailed comparative study of quadrature LC and RC oscillators, including cross-coupled LC quasi-sinusoidal oscillators, cross-coupled RC relaxation oscillators, a quadrature RC oscillator-mixer, and two-integrator oscillators; (3) a thorough investigation of the effect of mismatches on the phase-error and the phase-noise; (4) the conclusion that quadrature RC oscillators can be a practical alternative to LC oscillators when area and cost should be minimized (in cross-coupled RC oscillators both the quadrature-error and phase-noise are reduced, whereas in LC oscillators the coupling increases the phase-noise); (5) use of a structured design approach, in which a technology independent study, with ideal blocks, is performed initially, and then the circuit level design is addressed; (6) inclusion of many experimental results, obtained from different integrated circuit prototypes, in the GHz range.