Warehouse Management Systems: Functions, Selection & Trends

Introduction

The concept and use of warehousing has transformed significantly over the past decade. With increased competition and advancing technology, warehousing has become a decisive tool in the global market, serving as a mechanism to gain competitive advantage over rivals in product quality, advertising, pricing, and consumer services — whereas previously it served merely as a stock-keeping unit. This evolution has required restructuring and superior mechanization so that the outcomes achieved include higher production output at lower costs (Nynke, 2005).

The process of warehousing requires all the essentials needed by any other production process — that is, precise and timely data on merchandise, competitors, market prices, capital, and available developments for the correct and efficient implementation of warehouse services. The warehouse management system (WMS) is responsible for providing these facts. It takes on the task of supplying, accumulating, and describing all the necessary data to manage warehouse operations from the point of product arrival through to delivery (Nynke, 2005).

The importance of WMS has grown considerably to the point where, according to the Gartner Group, any company that does not incorporate WMS into its infrastructure is setting itself up for a disadvantage in the global market. Why has WMS grown so important over the past decade? After the implementation of an efficient WMS structure, companies experienced a range of positive outcomes: more intelligent use of available space, support for consumer EDI requirements, a decrease in the number of registrations required, amplified production efficiency, lower prices, and reduced error rates (Nynke, 2005).

Scope of Warehouse Management Systems

The main and most essential task of a WMS is to manage the inflow and outflow of products through the accurate use of relevant data. The position of WMS within the production process requires it to communicate and coordinate with other processes and personnel, including the assembly section, financial officers, merchandise approval, transportation and infrastructure departments, security, and industrial control structures such as AS/RS management and PLC systems — all in support of timely product delivery. Most of these processes can be incorporated into one industrial component called an enterprise resource planning (ERP) system; in simpler terms, the WMS must maintain constant and clear contact with ERP systems in order to carry out its functions competently (Nynke, 2005).

There is relatively little similarity between the operations and scope of an ERP system and those of a WMS. The origins of WMS were triggered by parallels in the data needed, the procedures, the management requirements, and ERP processes. ERP operations encompass long-term planning and management of all significant internal and peripheral business utilities. A WMS, by contrast, deals primarily with short-term preparation for the stocking of merchandise, the utilization of available space, and at times the delivery of merchandise. The foundational principles of a WMS were initially developed for a single large warehouse and then adjusted to meet the varying requirements of different warehousing environments (Nynke, 2005).

Functions of Warehouse Management Systems

Jacobs et al. (1997) and Baan (1998) (as cited in Nynke, 2005) both identify three core functional categories of the warehouse management system:

(1) Inter-warehouse organizational functions;
(2) Warehouse organizational functions; and
(3) Warehouse execution organizational functions.

These functions have been further subdivided to present a clearer picture of the overall process. Key subdivisions include: transforming or developing the operational facilities of warehouses — either under the administration of the primary warehouse, production centers, or contractors; tracking stored products and their categories with the required information on price, variety, and ABC assessment, along with the variety of merchandise demanded by customers; monitoring the flow and sales of all products to assist management in future decision-making; and tracking warehousing facility groupings alongside transportation and infrastructure costs (as cited in Nynke, 2005).

Warehouse organizational functions are further subdivided into: daily movement inspections, including incomplete orders and the filing of required documents; operational summaries of varying kinds, such as truck departures or delivery timelines; accounts needed for sustained effectiveness, including task allocation and rapid adjustments; careful analysis of capital and its appropriate use; analysis of diverse storage sectors including scope, stock-storage regulations, carriage plans, and storage conditions; and assessment of products that are out of demand, declining in demand, outdated, or dormant, followed by appropriate action (as cited in Nynke, 2005).

The warehouse execution function is a considerably more expansive process. It includes, broadly speaking, functional preparation, implementation, and management of the overall setup. These include: managing all tasks directly or indirectly related to customs or tax-connected actions; careful examination and administration of products to determine their future handling; formulating tactics for controlling the inflow and outflow of stored products and their placement within the facility in accordance with regulations; planning control service activities; parceling or re-parceling products for safety during shipping; managing stock movement into, within, and out of the facility including transportation to different markets or consumer targets; handling shipping procedures including stacking, unloading, customs clearance, and invoicing; conducting physical analysis of stock along with scheduling, recording, and on-site validation; administering a system that manages pick stock individually or from whole volumes of products; and managing the collection and registration of data from the moment a product is reported as shipped toward the dock. This last process involves managing the loading of products off ships into the warehouse with validation from the primary procurement contract — whether from a contractor, another warehouse as a replacement, a dissatisfied customer, or a product returned from markets due to inactivity or declining demand. Every unanticipated product return must undergo identification and authentication for re-procurement after the collection of relevant data (as cited in Nynke, 2005).

Evaluating Düsseldorf's (1996; as cited in Nynke, 2005) classification framework, three types of WMS can be identified: basic, advanced, and complex, each with its own characteristics and responsibilities. A basic WMS manages only a small segment of the overall process — in most cases, storage and location organization alone — making it straightforward in scope and focused on throughput. A basic WMS uses inspection setups to identify goods in storage, determine their arrangement within the warehouse, and catalog them, while also establishing norms for loading and unloading using RF systems. An advanced WMS takes this a step further by adding storage and space assessment to its responsibilities — that is, it plans the use of available assets and manages the daily movement of products into and out of the warehouse. A complex WMS represents the full amalgamation of planning, implementation, and management of functions across a group of warehouses. This type can utilize advanced technologies such as AS/RS, sorters, AGVs, and robots, while also incorporating peripheral tasks such as shipping scheduling, product location, inflow and outflow preparation, value-added logistics planning, and the development of regulatory operations across warehouses as a whole (as cited in Nynke, 2005).

Each organization has its own unique needs and therefore requires a WMS that is best compatible with its organizational structure. Both primary and secondary drivers must be considered when making this selection.

Conclusion

The evolution of warehouse management systems reflects a broader shift in how organizations compete globally. WMS has moved from a simple inventory tool to a complex, technology-driven strategic asset. Understanding its scope, functions, and selection criteria — as well as the emerging trends shaping its future — is essential for any organization seeking to optimize supply chain performance and maintain a competitive edge in the global market.