This review discusses gas sensors based on conducting polymers such as polyaniline (PANI), polypyrrole (PPy), and poly(3,4-ethylenedioxythiophene) (PEDOT). The review covers the sensing mechanisms, configurations, and performance factors of these sensors. It also addresses the disadvantages of these sensors and outlines future research directions. Conducting polymers are attractive for gas sensing due to their high sensitivity, fast response times, and ability to operate at room temperature. They are easy to synthesize and modify, and their mechanical properties allow for flexible sensor fabrication. The review highlights the importance of doping in enhancing the conductivity of these polymers and explains how different analytes interact with conducting polymers through redox reactions, proton transfer, and weak physical interactions. The sensing mechanisms involve changes in electrical resistance, capacitance, and inductance, which can be measured to detect gases. Different sensor configurations, such as chemiresistors, transistors, and diodes, are discussed, along with their advantages and limitations. The review also covers optical sensors using UV-vis and NIR spectroscopy, and surface plasmon resonance (SPR) for gas detection. Overall, conducting polymers offer promising alternatives to traditional gas sensors due to their versatility, cost-effectiveness, and performance characteristics.This review discusses gas sensors based on conducting polymers such as polyaniline (PANI), polypyrrole (PPy), and poly(3,4-ethylenedioxythiophene) (PEDOT). The review covers the sensing mechanisms, configurations, and performance factors of these sensors. It also addresses the disadvantages of these sensors and outlines future research directions. Conducting polymers are attractive for gas sensing due to their high sensitivity, fast response times, and ability to operate at room temperature. They are easy to synthesize and modify, and their mechanical properties allow for flexible sensor fabrication. The review highlights the importance of doping in enhancing the conductivity of these polymers and explains how different analytes interact with conducting polymers through redox reactions, proton transfer, and weak physical interactions. The sensing mechanisms involve changes in electrical resistance, capacitance, and inductance, which can be measured to detect gases. Different sensor configurations, such as chemiresistors, transistors, and diodes, are discussed, along with their advantages and limitations. The review also covers optical sensors using UV-vis and NIR spectroscopy, and surface plasmon resonance (SPR) for gas detection. Overall, conducting polymers offer promising alternatives to traditional gas sensors due to their versatility, cost-effectiveness, and performance characteristics.