6. Conclusions and opportunities for research
In this article, we have reviewed and categorized the articles published between 1998 and 2013 that used
simulation optimization to solve inventory replenishment problems. We have shown that this approach has become
increasingly popular in domain-focused articles; in different fields within inventory management (such as transshipment
and spare parts inventory management), researchers have started using simulation optimization to solve practical
problems that, without simplifying assumptions, are far too complex for analytical techniques. In spite of this, we
found (somewhat surprisingly) that most of the solved inventory problems continue to be based on relatively simple
supply chain structures consisting of a single echelon, often with deterministic (or even negligible) lead times. Since
multi-echelon problems with stochastic lead times are common in practice, this gap indicates an attractive area for
further research.