How long should a backlog be?

Long enough to hold the next few months of likely work in decreasing detail, and short enough that the owner can say why every item is where it is. Hundreds of items nobody can justify are a sign that adding has replaced ordering.

Who can add to the backlog?

Anyone, in most teams, and that is fine. Adding is a request. Only the owner orders, and only the owner decides whether an item stays. The distinction between adding and ordering is what keeps the list a backlog.

What is backlog refinement?

The ongoing work of breaking down, clarifying and estimating items near the top so they are ready when planning arrives. It is an activity, not an event, and the guide leaves its shape to the team; a session or two a week is typical.

Product Backlog

Also: backlog, backlog refinement, backlog item, product goal, prioritisation

A product backlog is the single ordered list of everything that might be done to improve a product, owned by one person who decides the order, refined continuously, and drawn from when each iteration is planned.

Assessment. A backlog is only a backlog if one person orders it and the order means something. A list of four hundred items that a committee adds to and nobody removes from is a wish list with a tool licence, and the team drawing from its top is drawing from whoever shouted last. Ordering is the job; adding is what everyone else does.

Everything a product might need, in one list, in order. The top items are small, clear and ready to build; the bottom items are large, vague and may never be done; and the gradient between them is the product of continuous refinement, in which the team and the owner break large items down, clarify what each means, and estimate what they can. The owner decides the order, taking whatever advice they like, and the team takes work from the top at each iteration's planning. That is the mechanism by which agile delivery controls scope: not by baselining a specification, but by deciding, repeatedly and visibly, what comes next.

Position in the list	What the items look like	Who is working on them
Top	Small, clear, estimated, ready to build this iteration	The team, in planning
Upper middle	Understood, possibly still too large, being split	The team and the owner, in refinement
Lower middle	Ideas with a rationale, not yet examined	The owner, ordering
Bottom	Large, vague, speculative; may be deleted	Nobody, deliberately

The order expresses the product strategy, and the product goal, a statement of where the product is heading, is what the order should serve. Ordering is not sorting by who asked loudest, nor by estimated size, nor by a formula; it is the owner's judgement about value, risk, dependency and learning, made with the team's input and owned alone. The Scrum guide makes the owner accountable for exactly that and forbids delegating the ordering to a committee, because a committee produces an average and a product needs a direction. The product owner assessment tests this harder than anything else, and practitioners whose backlogs are ordered by steering group fail it.

In practice

One sentence of product goal, so the order has something to serve.
Three hundred deletions, none of them missed.
Adding is a request; ordering is a decision, and the departments learned the difference in a week.

A team's backlog holds six hundred items collected over three years, each added by a department and none ever removed. Planning takes a day because the top of the list is whatever was added most recently, and the team has no idea why any item matters. The new product owner spends a week doing three things: writing a product goal in one sentence, deleting everything more than a year old that nobody can argue for, and ordering the remaining eighty by that goal. Planning drops to two hours, the team can say why each item is next, and the departments learn that adding an item is a request rather than a decision. Three hundred deleted items are never mentioned again.

What the departments learned

Anyone may add an item; only the owner decides where it sits and whether it stays. Once that distinction was visible, requests kept arriving and the list stopped growing, because a request that never reaches the top is answered by its position.

Often confused with

Work Breakdown Structure (WBS): A breakdown structure is a fixed hierarchy of what will be delivered, baselined and controlled. A backlog is a living ordered list of what might be, reordered every iteration. Both prevent forgotten work; only one is a plan.
Sprint: The sprint backlog is the subset selected for one sprint, plus the plan for delivering it. The product backlog is the whole ordered list it was drawn from, and it outlives every sprint.
Change Control: In agile delivery the backlog is the change-control process: every request becomes an item and the owner's ordering is the decision. Continuous and single-owner instead of periodic and committee-based.

Key takeaways

→One list, one owner, one order; ordering is the job.
→Refinement makes the top small and clear and leaves the bottom vague on purpose.
→A backlog nobody deletes from is a wish list; the order should serve a stated product goal.

Related concepts

Part ofScrum
The ordered list of work Scrum draws from.
IncludesUser Story
The usual form of a backlog item.

Where this concept sits in the field

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FAQ

How long should a backlog be?: Long enough to hold the next few months of likely work in decreasing detail, and short enough that the owner can say why every item is where it is. Hundreds of items nobody can justify are a sign that adding has replaced ordering.
Who can add to the backlog?: Anyone, in most teams, and that is fine. Adding is a request. Only the owner orders, and only the owner decides whether an item stays. The distinction between adding and ordering is what keeps the list a backlog.
What is backlog refinement?: The ongoing work of breaking down, clarifying and estimating items near the top so they are ready when planning arrives. It is an activity, not an event, and the guide leaves its shape to the team; a session or two a week is typical.

Sources

The primary text this definition rests on. Read it before relying on this one.

Schwaber, K. and Sutherland, J., The Scrum Guide (2020)
Pichler, R., Agile Product Management with Scrum (2010)

Last reviewed 13 September 2026 · Getting Digital

Product Backlog

In practice

Often confused with

Key takeaways

Related concepts

Where this concept sits in the field

Certifications that test this

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FAQ

Sources