# Set up Extension Visibility

Out of the box, everyone in your organization can see every department or the default extension group in the Cloud Voice App, depending on whether organization management is turned on. When you need to hide certain extensions, departments, or groups from some users, create extension visibility rules to control exactly who sees what.

## Create a visibility rule

1. In the Cloud Voice portal, go to **Extension and Trunk > Client Permission > Extension Visibility**.

   The page opens with the built-in default rule already in place.

   ![Extension Visibility page showing the default rule that governs what users can see](/images/pbx/default-extension-visibility-rule.png)

2. Click **Add rule**.

3. Define the rule using the fields below, then click **Save**.

   ![Form for defining who a visibility rule applies to and which extensions they may or may not see](/images/pbx/set-up-extension-visibility-rule.png)

   :::tip
   Read every rule as two halves: the **Extension / Extension Group / Organization** field sets *who* the rule applies to, and **Objects** sets *what* those users are allowed or blocked from seeing. Keeping the who and the what straight is the easiest way to avoid building a rule that hides the wrong people's contacts.
   :::

   | Field | What it controls |
   |-------|------------------|
   | **Extension / Extension Group / Organization** | The users the rule applies to. Use the edit icon to choose either **All extensions** or **Specific extensions and extension groups/departments**. |
   | **Permission Type** | Whether the rule grants or blocks visibility. Choose **Allow view** to let the selected users see the objects in the rule, or **Disallow view** to hide those objects from them. |
   | **Objects** | The extensions, groups, or departments the rule covers. Use the edit icon to pick from **All extensions and extension groups/departments**, **Groups/Departments that the extension belongs to**, **Selected extensions and groups/departments**, or **Specific extensions and extension groups/departments**. |

   :::note
   Selecting a department automatically includes its sub-departments. Review your selection carefully before saving.
   :::

## Order your rules

Rules are evaluated from the top of the list downward. When two rules disagree about the same extension, the one higher in the list wins.

To reposition a rule, use the move-to-top, move-up, more, or move-to-bottom controls on that row.

:::caution
Because higher rules override lower ones, confirm the order matches the outcome you intend whenever you add or edit a rule.
:::

## Result

In the Cloud Voice App, each user sees only the extensions, groups, and departments your rules make visible to them.

:::caution
Hiding an extension also blocks calling it: users cannot place calls to extensions they are not permitted to see. Keep this in mind if you only meant to declutter someone's contact list.
:::