Photo by Robyn Budlender on Unsplash

Product Backlog vs Sprint Backlog

In a nutshell, in Agile Scrum, the difference between the Product Backlog vs Sprint Backlog is:

The Product Backlog is the entire list of User Stories (features) requested to be included in the product. It is prioritized sequentially based on business value, cost to implement and risk.

The Sprint Backlog is the list of User Stories that have been pulled from the Product Backlog into a Sprint. The Sprint Backlog forms the sprint forecast, the work the team expects to deliver in the sprint (formerly known as the Sprint Commitment).

Product Backlog

The Product Backlog is the responsibility of the Product Owner. A high quality backlog is hierarchical, instead of a flat list (see User Story Mapping).

While coding (build) can begin as soon as enough stories are identified to fill a sprint, I recommend spending some time in a Discovery Phase to build out a Product Vision, user personas, and enough User Stories for at least 3 sprints. Keeping up with the build team is a constant challenge for a Product Owner, so get this foundational elements in place before building.

The Product Backlog continues to grow and change during the product as the Product Owner and team learn from what is built and how users accept and work with the product. Manging the Backlog is known as Backlog Grooming.

Sprint Backlog

The Sprint Backlog is formed during Sprint Planning. User Stories in the Sprint Backlog are sorted in priority order as they are in the Product Backlog. Generally, stories are pulled from the Product Backlog in priority order. Sometimes this is negotiated in the planning meeting if, for example, the next highest priority story doesn’t fit nicely based on its estimated size (see Planning Poker).

This image from my post on Sprint Planning shows the process

During the sprint, stories should be built and completed based on sprint backlog priority. At the end of a sprint if only the lowest priority story in the sprint is completed, please discuss this in the retrospective and ensure this principle is understood.

Summary

The 2 backlogs in Agile Scrum are the Product Backlog and the Sprint Backlog. The Product Backlog is the full list of User Stories to be delivered. It is prioritized by business value and feeds the Sprint Backlog in sprint planning. The Sprint Backlog is forecasted to be completed by the team within the duration of the sprint.