💡 Why both documents matter
In traditional project management, everything starts with a detailed business case — a thick document that tries to predict every cost, risk, and benefit before a single line of code is written.
In Lean and Agile environments, we take a different approach. We still need to justify the investment, but we do it just enough to make an informed decision, and then move fast to validate our assumptions.
That’s where the Lean Business Case comes in. It helps leaders decide whether an Epic — a big, strategic initiative — is worth pursuing. Once approved, that Epic gets broken down into smaller, deliverable Features, each defined through a Product Requirements Description.
Together, they answer the two fundamental questions every product team must get right:
Why are we building this?
What exactly are we building?
💼 The Lean Business Case: Defining the “Why”
In SAFe (Scaled Agile Framework), every major initiative at the portfolio level begins as an Epic. But not all Epics are created equal — and not all deserve investment.
The Lean Business Case helps teams and executives quickly assess if an idea is worth funding and testing. It’s a lightweight document, usually one or two pages long, that focuses on value, not volume.
A Lean Business Case includes:
Epic description: What this initiative is about
Problem or opportunity: The business challenge or gap
Proposed solution: A high-level idea of how to solve it
Benefit hypothesis: What value we expect to deliver and how we’ll measure it
MVP definition: The smallest experiment we can run to test our assumptions
Cost and duration estimate: Rough effort and time needed
Success criteria: How we’ll know it worked
Think of it as a go/no-go filter. If the hypothesis looks strong enough, the Epic is approved and funded. If not, it’s parked — no wasted effort.
🧠 Example:
Epic: “Automate customer onboarding to reduce setup time by 50%.”
Benefit hypothesis: “If we reduce manual steps, customers will activate faster, improving retention and freeing up support time.”
🧩 From Epic to Feature: Moving to the “What”
Once an Epic has a green light, it’s broken down into smaller, deliverable chunks called Features.
Each Feature lives at the Program Level and fits within a Program Increment (PI) — typically 8 to 12 weeks of work for an Agile Release Train (ART).
Here’s where the Product Requirements Description (PRD) comes in.
While the Lean Business Case explains why an Epic should exist, the PRD (or Feature Description in SAFe terminology) explains what needs to be built to realize part of that Epic.
A Feature Description usually contains:
Feature name
Description (what it does and for whom)
Benefit hypothesis (linked to the Epic’s business case)
Acceptance criteria (conditions of satisfaction)
Dependencies or constraints
It’s practical, short, and meant for the product and development teams — not executives.
This is the document teams use to design, develop, and test the solution.
🧩 Example:
Feature: “Create an API for automated account creation.”
Benefit hypothesis: “This API will remove manual steps and reduce onboarding time by 30%.”
Acceptance criteria: “Admin users can create an account through the API with full validation and confirmation email.”
🔗 How they connect in the SAFe flow
Here’s how the two artifacts align in the overall SAFe hierarchy:
The Lean Business Case provides strategic direction.
The PRD translates that strategy into actionable requirements.
Together, they ensure that everyone — from executives to developers — stays aligned on why the work matters and what needs to be done.
🚀 Why this approach works
Keeps documentation lean — only what’s necessary to decide and build.
Maintains alignment — strategy connects directly to execution.
Encourages learning — the MVP validates assumptions early.
Speeds up delivery — smaller Features flow faster through ARTs.
Improves decision-making — investments are based on data, not opinions.
In other words, you stop building things because someone thinks they’re a good idea, and start building because the data says it’s worth testing.
✅ Final thoughts
In the world of Agile and SAFe, it’s not about creating more documents — it’s about creating the right ones.
The Lean Business Case gives you the confidence to invest wisely.
The Product Requirements Description gives your teams the clarity to deliver effectively.
When you connect the “why” to the “what,” you turn strategy into real customer value — and that’s what agility is all about.