This article reviews the evolution, design and performance of CMOS low noise amplifiers for a wide variety of architectures. The review discussion encompasses common source (CS) and common gate (CG) design approaches with single and dual signal paths, passive and active feedback, passive and active bias, and various noise cancellation techniques. The relative performance impacts and tradeoffs for the each design approach are thoroughly tabulated with careful presentation of the relationships between gain, noise figure and linearity for a large number of implementations. Finally, the review explores next generation LNA developments and future research opportunities.