The book first summarizes the various factors contributing to calculi formation, along with different therapeutic measures including medicinal plants/drugs which have been experimentally proven to exhibit antiurolithiatic activity employing various mechanisms. The authors discuss the known transition metal oxalates, their synthetic analogues, thermal and magnetic behaviour, and reaction pathways, particularly for energy materials such as Li ion, as well as supercapacitor and redox flow battery systems. A number of possible synthetic pathways for the generation of oxalic acid in plants and fungi are presented and briefly discussed. An important number of studies have shown that ascorbic acid is the major substrate for the synthesis of oxalic acid in plants. Therefore, the so called "Wheeler-Smirnoff" mechanism, which explains the biosynthesis of ascorbic acid in the plant kingdom, is discussed in detail. Lastly, this compilation explores how hyperoxaluria can be a pathway through which kidney dysfunction occurs in persons due to diabetes mellitus or obesity and thus lead to a gradual deterioration of renal function.