Scrum

By Allen Jay Bercero

Scrum is a lightweight agile framework for developing complex products, in which a small team works in fixed-length cycles called sprints to deliver a usable increment, then inspects and adapts. It is the most widely adopted way of “doing agile.”

Scrum is deliberately minimal: it defines a handful of roles, meetings, and artifacts and then stops, leaving the team to fill in how they design, code, and test. That’s why it’s a framework, not a methodology. It’s a skeleton you flesh out, not a complete recipe.

Also known as

Scrum framework · (loosely and technically incorrectly) “the Scrum methodology” The name comes from rugby, where the team packs together to restart play, a metaphor from a 1986 Harvard Business Review article by Takeuchi and Nonaka.

Don't confuse with

  • Scrum (the framework) vs Agile (the broader mindset). All Scrum is agile; not all agile is Scrum.
  • Scrum vs Kanban. Both are agile, but Scrum uses fixed sprints and defined roles; Kanban uses continuous flow and none of Scrum’s roles/events.

The empirical foundation

Scrum is built on empiricism: knowledge comes from experience and decisions are based on what’s observed. This rests on three pillars:

  • Transparency: the work and progress are visible to everyone.
  • Inspection: artifacts and progress are checked frequently.
  • Adaptation: when something’s off, adjust quickly.

Its five values give the culture that makes this work: commitment, focus, openness, respect, courage.

The Scrum Team

One small team (the 2020 Scrum Guide recommends 10 people or fewer), with no sub-teams and no hierarchy. It has three accountabilities (the current official word; older material says “roles”):

AccountabilityOwnsAlso known as / watch out
Product Owner (PO)What gets built and in what order; maximizes product value; owns the Product backlog.Often confused with Product Manager, related but not identical; at some companies one person does both.
Scrum MasterThe team’s effectiveness; coaches Scrum, removes impediments, protects focus. A servant-leader, not a boss.Frequently mislabeled “project manager,” “delivery lead,” “iteration manager,” or “agile coach.”
DevelopersHow the work gets done; they build the increment. Includes everyone doing the work: engineers, designers, testers.Called the “Development Team” before the 2020 guide.

The team is not a hierarchy

The Scrum Master does not manage the Developers, and the Product Owner is not their boss. The three accountabilities are about ownership of different concerns, not rank.

The five events

All events happen inside the Sprint, which is itself the container event.

EventPurposeTimingAlso known as
The SprintThe fixed time-box (1 month or less) that holds all other events; produces one increment.Continuous, back-to-back”iteration,” “cycle”
Sprint planningDecide the Sprint Goal and select backlog items to build.Start of sprint”planning,” “the planning meeting”
Daily Scrum15-minute team sync to inspect progress toward the Sprint Goal and re-plan the day.Every day”standup,” “daily standup,” “morning sync,” “roll-call”
Sprint reviewShow the finished increment to stakeholders and get feedback; adapt the backlog.End of sprint”demo,” “sprint demo,” “show and tell”
Sprint retrospectiveThe team improves itself: its process, tools, and collaboration.After the review”retro”

The two end-of-sprint meetings everyone mixes up

Sprint review is about the product (did we build the right thing? Stakeholders attend). Sprint retrospective is about the team’s process (how do we work better? Team only). Also: a retrospective is not a post-mortem. Retros are regular and forward-looking; a post-mortem is a one-off analysis after an incident or a project ends.

Myth: the "three questions"

Older Scrum described the Daily Scrum as everyone answering “what did I do yesterday / today / any blockers?” The 2020 Scrum Guide dropped that as a requirement. The daily is whatever helps the team hit the Sprint Goal. Many teams still use the three questions out of habit.

The three artifacts (and their commitments)

Each artifact has a “commitment”, a target that gives it focus (added in the 2020 guide):

ArtifactWhat it isCommitment
Product backlogThe single ordered list of everything that might be built.Product Goal: the long-term objective.
Sprint backlogThe items chosen for this sprint, plus the plan to build them.Sprint Goal: the one objective of this sprint.
IncrementThe sum of completed work; a usable, potentially shippable step toward the Product Goal.Definition of Done: the shared checklist that makes work “done.”

Definition of Done vs Acceptance Criteria

Definition of Done (DoD) is team-wide, the same quality bar for every item (tests pass, code reviewed, deployed to staging…). Acceptance criteria are per-story, the specific conditions that one User story must satisfy. An item can meet its acceptance criteria but still not be “done” if it fails the DoD.

A sprint, start to finish

One two-week sprint

  1. Sprint planning (Mon, wk 1): team picks a Sprint Goal and pulls items from the Product backlog into the sprint backlog.
  2. Build (wk 1–2): Developers design, code, and test the increment. Each morning: a 15-min Daily Scrum.
  3. Sprint review (Fri, wk 2): demo the working increment to stakeholders; gather feedback.
  4. Retrospective (Fri, wk 2): team agrees on one or two process improvements.
  5. Next sprint starts Monday. Repeat.

Scaling Scrum

For many teams on one product, organizations use scaling frameworks: Nexus, LeSS (Large-Scale Scrum), SAFe (Scaled Agile Framework), or Scrum@Scale. Scrumban blends Scrum’s cadence with Kanban’s flow.

See also

References