Purpose of Product Backlog Refinement
The purpose of Product Backlog Refinement is to add details, estimates and order to the Product Backlog and it’s Product Backlog Items. During Product Backlog Refinement, items are reviewed and revised.

Time-box
Product Backlog Refinement isn’t an official Scrum Event, so there is no official time-box. The guideline for Product Backlog Refinement however is that it usually takes no more than 10% of the Development Teams’ capacity.

Attendees
The Scrum Team decides how and when Product Backlog Refinement is done. Typically, the Product Owner is in the lead, since the Product Owner is responsible for the Product Backlog. However, the Scrum Team together decides how and when to plan Refinement meetings. Optionally, the Scrum Team may also invite people outside the Scrum Team to Refinement, such as experts or stakeholders, in order to gain technical, business or domain advice.

Inspect
During Product Backlog Refinement, the following is being Inspected:

  1. The Product Backlog (adding new items, changing the ordering and removing items for example);
  2. The contents of the Product Backlog Items (by adding details and estimates for example or by slicing bigger items into smaller items);

Adapt
During Product Backlog Refinement, the following is being Adapted:

  1. The Product Backlog (adding new items, changing the ordering and removing items for example);
  2. The contents of the Product Backlog Items (by adding details and estimates for example or by slicing bigger items into smaller items);

Meeting Flow
There are many ways for conducting Product Backlog Refinement meetings. I typically split the meeting flow of a Product Backlog Refinement meeting into three parts:

  1. Before the meeting;
  2. During the meeting;
  3. After the meeting;

Below you will find a flowchart of each of the three parts.

Refinement-Before-Meeting-Flowchart

Refinement-During-Meeting-Flowchart

Refinement-After-Meeting-Flowchart