Steroids play important roles in the human body, including, but not limited to: controlling meiosis, fat storage, protein and carbohydrate metabolism, muscle growth, immune function and nerve cell membrane chemistry. Almost one-third of all currently prescribed medications contain steroid skeleton e.g. Proellex, Chronocort, Corticosteroids etc. Many medicinally important steroid derivatives do not occur in nature and must be synthesized in the laboratory. The modification of steroid skeleton or fusion of any heterocyclic ring system such as triazolidinones, oxathiolanes, and carbohydrate group, to steroid was found to augment the biological and industrial revolution as it results in change of electronic and molecular properties and have shown marked biological activities like anti-cancer, antimicrobial, antimalarial and anti-HIV. Thus, innumerable methods are necessary to develop across to find the better analogues of steroid natural products to show the potent biological activities. The purpose of the present book is to incorporate advances in the area of organic synthesis.