Picture a small garment workshop. The warehouse is always packed, yet when a customer order arrives, the exact thread colour needed is nowhere to be found. The owner says there is too much stock; the accountant says there is no cash. Both are right. The problem is not too much inventory in general — it is too much of the wrong inventory. This is exactly where MRP (Material Requirements Planning) comes in. This article explains how an MRP program puts inventory decisions on a factual footing and what that means for the money in your pocket.
At its core, MRP answers one question: which materials do I need to order, when, and how much? To answer it, the program looks at two things. First, your confirmed sales orders or production schedule — what you plan to make or sell. Second, the bill of materials, which lists every component that goes into each product. The program combines these two inputs and tells you: ‘You need to order this much of this material by this date.’ The result is a purchasing plan driven by real demand, not guesswork.
Safety stock is the next piece of the puzzle. Safety stock is the buffer you keep on hand in case a supplier runs late or demand spikes unexpectedly. Most small businesses set this number by instinct: ‘We got caught short last season, so let us keep more this time.’ The outcome is predictable — materials sitting in the warehouse for months, financing costs accumulating on idle inventory, and cash tied up that could be working elsewhere. An MRP program approaches safety stock differently. It looks at how long suppliers typically take to deliver and how much demand fluctuates from period to period, then proposes a buffer quantity based on that data rather than gut feeling.
Order quantity decisions shift in the same way. Ordering in bulk looks attractive because it brings down unit shipping costs. But a large order means materials sitting in storage for a long time. When you add warehousing costs, insurance, the risk of spoilage or obsolescence, and the return you could have earned on that capital elsewhere, the advantage of bulk ordering often disappears. MRP programs handle this trade-off through an EOQ (Economic Order Quantity) calculation. The formula compares the cost of placing an order against the cost of holding inventory and finds the quantity that minimises the total. The calculation runs inside the program; all the user has to do is enter accurate data.
The impact of all this on the business shows up in inventory turnover — a ratio that tells you how many times your stock converts into sales within a year. If your annual cost of goods sold is 600 million lira and your average inventory value is 200 million lira, your turnover ratio is 3. Raising that ratio to 4 brings average inventory down to 150 million lira. The 50 million lira difference is no longer sitting in the warehouse. It is available for payroll, supplier payments, or new orders. In the economic conditions of 2001, with credit costs running high, that kind of freed-up cash is not an abstract figure — it is real breathing room for a small business.
Setting up an MRP program and keeping it running is not a simple task. The system produces accurate results only when it receives accurate inputs. Bills of materials must be complete and up to date. Supplier lead times must be entered into the system. Physical stock counts must be done regularly so that the program knows what is actually on the shelf. If any of these inputs are missing or wrong, the program produces wrong recommendations. In most businesses, the first months after installation are spent cleaning up this data. Completing that process without support from a local reseller or consultant is very difficult. There is also a human side: the purchasing manager and the production supervisor need to trust the system enough to follow what it recommends, and that confidence takes time to build.
For a small or mid-sized business owner thinking about investing in an MRP program, three questions are a good place to start. Are your bills of materials — the lists of what goes into each product — recorded anywhere in a computer system? Do you know the average delivery time for each of your main suppliers? How many times last year did you face either ‘no material, production stopped’ or ‘warehouse full, no cash left’? If your answer to the first two questions is no, the groundwork comes before the software. Your answer to the third question shows how much the program could save you. In a business where inventory problems are a recurring reality, an MRP system tends to pay for itself quickly.
This article was originally written in Turkish by Gökhan MERCANOĞLU on July 16, 2001 and has been automatically translated into English and other languages using machine translation.