This book is focused on study of the two levels of inventory models . Various inventory models considering Stock dependent demand with preservation technology, Ramp type demand with bulk release, Probabilistic demand with uniform distribution having shortages are discussed. This book attempts to find an optimal solutions for each of the models. The book illustrates numerical solutions of the two levels of inventory models under different demand situations for both deterministic and probabilistic. Numerical illustrations and Sensitivity Analysis for each model are done and appropriate...