Foreword

Warehousing is one of the most important and critical logistic activities in industrial and service systems. A few production philosophies, e.g. just in time (JIT) and lean manufacturing, propose and support the so-called ‘‘zero stock’’ as basic and strategic pillar. Also manufacturing requirement planning (MRP), the well known and widely adopted ‘‘push-’’ based fulfillment technique, theoretically guarantees no storage quantities when the ‘‘lot for lot’’ reorder policy is adopted. Nevertheless, these special production systems do not operate in absence of warehousing systems that support and smooth the discontinuity of flow materials, products and components, at the input and at the bottom of a generic production stage.