Mild steel (MS) is the material of choice to fabricate various reaction vessels, pipes, tanks etc., in most of the chemical industries due to its easy availability and low cost. Hydrochloric acid and Sulphuric acid are generally used for the removal of undesirable scale and rust in several industrial processes. MS suffers severe corrosion in aggressive media. Many heterocyclic compounds have been proved to be effective inhibitors for the corrosion of metals and alloys in acid media. There has been a growing trend in the recent years to go in for eco-friendly, non-toxic green inhibitors in place of synthetic substances which suffer from many drawbacks. This book discusses the anticorrosion effect of the following alkaloidal plants viz.,Datura metel, Datura stramonium, Solanum nigrum, Solanum tuberosum, Piper nigrum, Rauvolfia serpentina and Strychnos nux-vomica and their corresponding alkaloid constituents viz.,Atropine, Solasodine, Piperine,Reserpine and Brucine against mild steel corrosion in acid media. Further, this study has unearthed another facet of the alkaloids viz., the corrosion inhibition potential as so far only their physiological effects are studied.