> ## Documentation Index
> Fetch the complete documentation index at: https://confidence.spotify.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Organize Experiments with Surfaces

> Tie experiments to surfaces to coordinate scheduling and prevent conflicts between overlapping changes.

Tie an experiment to a surface to let others working on that surface see your experiment. This
allows you to plan experiments better. If you experiment on the same part of an app or a page, or if
there's another reason your experiments mustn't collide, you can coordinate them using exclusivity
tags. You can also decide to run them at distinct points in time.

Interaction effects between experiments are rare, see
[this report](https://www.microsoft.com/en-us/research/group/experimentation-platform-exp/articles/a-b-interactions-a-call-to-relax/)
by Microsoft. For this reason, many companies, including Spotify, only coordinate experiments that
directly influence each other. For example, if two teams work on the design of a page and the work
by one of the teams is only functional if the other team's work doesn't change the page, they should
coordinate their experiments.

## The Global Surface

Every account has a global surface. All experiments are automatically part of the
global surface and it's impossible to run experiment outside of this surface.
Use this surface to configure settings that should apply to all your
organization's experiments.

## Create Surfaces

<Tip>
  Give your surfaces names that:

  * are self-explanatory, so that people from different parts of the organization can understand what
    the surface is and what it isn't
  * don't use organization-specific words, as the structure of the organization often changes more
    often than the product structure

  Describe your surfaces with:

  * a short sentence about what the surface is
  * examples of typical experiments that should run on this surface
  * examples of experiments that you suspect your colleagues might think should run on this surface, but that in fact shouldn't
</Tip>

<Example title="Example surfaces">
  For an e-commerce website, examples of surfaces could be:

  * Home page
  * Checkout
  * Products
  * Search
  * Customer support

  Each surface is its own area in the product. Multiple teams can work on the same surface.
</Example>

Experiments can belong to multiple surfaces at the same time. All experiments belong to the global surface.

### Surface Size

When you start to exceed 30-40 live experiments in a surface at any given time, you should consider
splitting up the surface into smaller surfaces to lower the load of the experimenter. The purpose of
surfaces is to make it easier for experimenters to keep track of experiments that are relevant for
their experiment. If there are too many experiments on a surface, this is overwhelming.

## Use Surfaces to Coordinate Experiments

Create exclusivity groups and holdbacks on surfaces to coordinate experiments.
Go to the **Surface** tab and click *Settings* in the top right corner.

Watch this video to get a quick overview of how to use exclusivity groups to coordinate experiments in Confidence.

<iframe className="w-full aspect-video rounded-xl" src="https://www.youtube.com/embed/8UTi93Yx5vk?si=JPm2V5hokeftz-f4" title="YouTube video player" allow="accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture" allowFullScreen />

Learn how to create exclusivity groups and holdbacks in the [documentation](/docs/experiments/exclusive-experiments).

## Related Resources

<CardGroup cols={2}>
  <Card title="Surfaces Introduction" href="/docs/surfaces/introduction">
    Overview of surfaces in Confidence
  </Card>

  <Card title="Surface Settings" href="/docs/surfaces/surface-settings">
    Configure surface settings
  </Card>

  <Card title="Exclusive Experiments" href="/docs/experiments/exclusive-experiments">
    Make experiments mutually exclusive
  </Card>

  <Card title="A/B Tests" href="/docs/experiments/workflows/abtests">
    Run A/B tests on surfaces
  </Card>
</CardGroup>
