This book proposes new transformation algorithms to transform op-amp circuit into equivalent circuit utilizing other active blocks.The first part proposes a genetic methodology based on genetic algorithm (GA) and symbolic analysis to transform op-amp circuits into Second Generation Current Conveyor (CCII) and Transconductance Amplifier (TA) ones. This methodology is applied on op-amp-Gyrator circuit. It is also applied on KHN and TT circuits.The second part of the book introduce a modified version of differential difference current conveyor transconductance amplifier (DDCCTA) block. This active block is used to realize the TT and KHN circuits.