MRP vs. MRP 2 System – What Is It and What Are the Differences?

Manufacturing Resource Planning (MRP 2) is a direct development of the MRP concept (MRP I, MRP 1). It is an essential element of the IT infrastructure for manufacturing companies. In this article, we analyze the functionality of the MRP system and what is worth knowing when choosing a solution to support production processes.

MRP (Material Requirements Planning) is a method used to precisely calculate the materials and components needed to manufacture a product.

The MRP method functions both as a theoretical planning concept and as advanced software. In a systemic approach, it is most commonly found in three forms:

• As an element of integrated ERP systems,
• As part of Capacity Requirements Planning (CRP) systems,
• As a standalone, dedicated MRP system.

In the classic approach, the MRP 1 method is based on the "push" model. This means that the demand for raw materials is determined in advance based on sales forecasts. Goods are then produced or purchased according to the "make or buy" principle to meet the predicted demand.

Modern production management systems also include modules such as:

• Financial and sales planning,
• Strategic management,
• Shop Floor Control (SFC) – enabling the exchange of priority information between the planner and workstations.

In contrast, concepts like Lean Production operate on a "pull" model, where the production impulse comes from an actual order rather than a forecast.

MRP 2 (or MRP II) stands for Manufacturing Resource Planning. Its history began in the 1980s when it was developed as an extension of the MRP 1 method. At that time, it was intended to provide companies with planning for all resources, not just materials.

In addition to inventory, the MRP II system considers:

• Availability of machines and equipment,
• Human capital (labor force),
• Production capacities and schedules,
• Financial flows.

The MRP II system allows for the creation of production plans that take available resources into account. It determines:

• What resources are needed,
• In what quantity,
• And at what time.

MRP II also allows for identifying efficiency problems, detecting discrepancies between the plan and reality, and analyzing resource utilization.

MRP Example: A furniture manufacturer receives an order for 50 tables. The MRP system analyzes the Bill of Materials (BOM) and calculates that 200 legs and 50 tops are needed. The software checks inventory: there are 100 legs in stock. It then automatically generates a purchase order for the missing pieces and schedules the assembly start date so that raw materials arrive on time.

• Used in manufacturing enterprises.
• Can be part of an ERP system.
• Support production process control.
• Utilize production plans, BOMs, and inventory levels.
• Used to calculate material requirements.
• IT systems supporting management.

The most important difference lies in the functional scope:

• MRP (MRP I): Focuses on materials, plans material requirements, and does not cover full resource management.
• MRP II: Covers all production resources, integrates various departments (purchasing, finance, quality), enables process simulation, and supports capacity planning while considering market realities and demand.

No, but they are closely related. MRP focuses almost exclusively on production and material logistics. ERP software covers all areas of an enterprise through modular architecture (accounting, logistics, sales, HR, etc.). Today, MRP is simply a key module within broader ERP systems.

APS (Advanced Planning and Scheduling) systems are advanced tools for planning and scheduling. Unlike MRP II, they cover the entire supply chain and allow for more precise planning. APS helps coordinate actions between suppliers and production to avoid the "bullwhip effect."

• Advantages: Optimization of inventory, reduction of storage costs, elimination of downtime, and better order timeliness.
• Disadvantages: Sensitivity to data quality (inaccurate inventory leads to wrong plans) and the human factor (potential employee resistance).

MRP 2 is an evolution of MRP 1. These systems can be standalone or part of an ERP to ensure that materials are available for every stage of production. Modern firms typically use ERP systems with MRP/MRP II modules, often extended by APS for increased efficiency and control.