In the world of process improvement and quality management, understanding the flow of work through an organization is fundamental to achieving operational excellence. The Define phase of Lean Six Sigma methodology serves as the foundation for any improvement initiative, and within this phase, identifying upstream and downstream processes stands as a critical activity that can determine the success or failure of your project.
Understanding the Define Phase in Lean Six Sigma
The Define phase represents the first step in the DMAIC (Define, Measure, Analyze, Improve, Control) methodology. During this phase, project teams establish the groundwork for their improvement efforts by clearly articulating the problem, setting objectives, and mapping out the boundaries of their project scope. One of the most crucial activities within the Define phase involves identifying and documenting the upstream and downstream processes that interact with the process under investigation. You might also enjoy reading about Define Phase: Creating SMART Goals for Process Improvement Success.
Without a clear understanding of how processes connect and influence one another, improvement teams risk implementing solutions that may optimize one area while inadvertently creating problems elsewhere in the organization. This systems thinking approach ensures that improvements are sustainable and beneficial across the entire value stream. You might also enjoy reading about Affinity Diagrams in the Define Phase: Organizing Ideas and Requirements for Lean Six Sigma Success.
What Are Upstream and Downstream Processes?
Before diving into identification techniques, it is essential to understand what these terms mean in the context of process improvement.
Upstream Processes
Upstream processes are those activities that occur before the process you are examining. They serve as suppliers or inputs to your target process. These processes provide the materials, information, services, or approvals that your process needs to function properly. Any defects, delays, or variations in upstream processes will cascade forward and impact the performance of your target process.
Downstream Processes
Downstream processes are those activities that occur after your target process. They are the customers or recipients of your process outputs. These processes depend on the quality, timeliness, and accuracy of what your process produces. Problems in your target process will flow forward and affect downstream operations, potentially multiplying inefficiencies throughout the organization.
Real World Example: Order Fulfillment Process
To illustrate these concepts with practical clarity, let us examine a typical order fulfillment process in a manufacturing company. Suppose your target process is the “Warehouse Picking and Packing” operation.
Identifying Upstream Processes
In this example, the upstream processes that feed into warehouse picking and packing might include:
- Order Entry System: Where customer orders are received and entered into the system
- Credit Verification: Where customer payment terms and credit limits are confirmed
- Inventory Management: Where stock levels are tracked and picking lists are generated
- Production Planning: Where manufacturing schedules ensure products are available
- Quality Inspection: Where finished goods are verified before storage
Each of these upstream processes provides critical inputs. If the order entry system contains errors, warehouse staff will pick incorrect items. If inventory management data is inaccurate, pickers will waste time searching for products that are not where the system indicates. These upstream issues directly impact the efficiency and accuracy of the warehouse operation.
Identifying Downstream Processes
The downstream processes that receive outputs from warehouse picking and packing include:
- Shipping and Logistics: Where packed orders are dispatched to customers
- Invoicing: Where customers are billed for shipped items
- Customer Service: Where delivery confirmations and issue resolution occur
- Returns Processing: Where incorrect or damaged shipments are handled
- Accounts Receivable: Where payment collection is managed
If the warehouse picking and packing process makes mistakes, these errors flow downstream. Shipping sends wrong items to customers, invoicing bills for products not received, customer service spends time managing complaints, and returns processing experiences increased volume. The ripple effects can be significant and costly.
Sample Data Analysis: Understanding Process Relationships
Let us examine sample data that demonstrates the interconnected nature of upstream and downstream processes.
Consider a scenario where a warehouse operation is experiencing a high error rate. Over a three month period, the team collected the following data:
Warehouse Picking Accuracy Metrics:
- Total orders processed: 12,500
- Orders with picking errors: 875 (7% error rate)
- Average time to pick an order: 18 minutes
Upon investigation, the team traced the sources of these errors by examining upstream processes:
Upstream Process Issues:
- Order entry errors: 315 cases (36% of total errors)
- Inventory location inaccuracies: 280 cases (32% of total errors)
- Incomplete product descriptions: 175 cases (20% of total errors)
- Warehouse process errors: 105 cases (12% of total errors)
This data revealed that 88% of warehouse picking errors actually originated in upstream processes, not in the warehouse operation itself. Without identifying and mapping these upstream relationships, the team might have focused improvement efforts solely on warehouse training and procedures, addressing only 12% of the problem.
The downstream impact was equally revealing:
Downstream Cost Analysis:
- Customer service calls related to order errors: 625 calls at $15 per call = $9,375
- Return shipping costs: 480 returns at $25 per return = $12,000
- Restocking and reprocessing labor: 160 hours at $35 per hour = $5,600
- Rush shipping to correct errors: 285 shipments at $45 per shipment = $12,825
- Customer goodwill credits: $8,200
The total downstream cost of these warehouse errors amounted to $48,000 over three months, or $192,000 annually. This financial impact provided compelling justification for the improvement project and helped secure management support.
Techniques for Identifying Upstream and Downstream Processes
SIPOC Diagrams
The SIPOC (Suppliers, Inputs, Process, Outputs, Customers) diagram is one of the most effective tools for identifying process relationships. This high level process map forces teams to explicitly document who provides inputs to the process and who receives outputs from it. Creating a SIPOC diagram early in the Define phase ensures that all stakeholders understand the boundaries and connections of the target process.
Process Mapping
Detailed process maps or flowcharts extend beyond the target process to show handoffs and dependencies. By mapping several process steps before and after your target process, you create visibility into the broader value stream. This expanded view helps identify where delays, defects, or variations originate and where they cause the most damage.
Stakeholder Interviews
Speaking directly with people who work in adjacent processes provides invaluable insights. Upstream process owners can explain what challenges they face in providing quality inputs, while downstream process owners can describe how variations in your target process affect their work. These conversations often reveal hidden dependencies and unspoken workarounds that formal documentation may not capture.
Value Stream Mapping
For more complex improvement initiatives, value stream mapping provides a comprehensive view of material and information flow through multiple processes. This technique visually represents lead times, process times, inventory levels, and information systems across the entire value stream, making upstream and downstream relationships explicit and measurable.
Common Pitfalls to Avoid
When identifying upstream and downstream processes, teams frequently encounter several challenges that can undermine their efforts.
Insufficient Scope: Some teams focus too narrowly on the immediate inputs and outputs, missing important second or third order effects. An order entry error might pass through multiple processes before causing a visible problem, but understanding this chain of causation is essential for effective improvement.
Ignoring Information Flows: While material flows are often obvious, information flows can be equally important. Authorization processes, approval chains, and data systems represent critical upstream and downstream connections that may not be immediately visible but significantly impact process performance.
Overlooking Informal Processes: Many organizations have unofficial workarounds and informal communication channels that people use to get work done. These shadow processes may represent important upstream or downstream relationships that will not appear on official process documentation.
The Strategic Importance of Process Identification
Accurately identifying upstream and downstream processes during the Define phase delivers multiple strategic benefits. It prevents suboptimization, where improvements in one area create problems elsewhere. It helps secure buy in from adjacent departments whose cooperation will be essential for implementation. It ensures that measurement systems capture the right data from the right sources. Most importantly, it increases the likelihood that improvements will be sustainable because they address root causes rather than symptoms.
Organizations that excel at Lean Six Sigma understand that processes do not exist in isolation. Every process is part of a larger system, receiving inputs from suppliers and providing outputs to customers. The Define phase provides the critical opportunity to map these relationships, set appropriate boundaries, and establish the systems perspective that will guide the improvement initiative through all subsequent phases.
Take Your Process Improvement Skills to the Next Level
Understanding how to identify and analyze upstream and downstream processes is just one of many essential skills you will develop through comprehensive Lean Six Sigma training. Whether you are looking to launch your career in process improvement, enhance your current role, or drive transformation within your organization, professional training provides the knowledge, tools, and credentials you need to succeed.
Our Lean Six Sigma certification programs cover the complete DMAIC methodology, from Define through Control, with hands on practice using real world scenarios and industry standard tools. You will learn from experienced practitioners who bring years of implementation experience across diverse industries. The skills you develop will be immediately applicable to your workplace challenges, delivering rapid return on your training investment.
Enrol in Lean Six Sigma Training Today and gain the expertise to identify process relationships, eliminate waste, reduce variation, and drive measurable improvements that advance your career and transform your organization. Visit our website to explore certification levels from Yellow Belt through Master Black Belt and find the program that matches your goals and experience level.
