# Adding, Editing & Working with CrossLinks
The process of creating a CrossLink is analogous to uploading a new file to your Vault. The key difference is that instead of selecting a file from the local file system, you browse and select a source document from another Vault in the same domain.
Note: To create CrossLink documents, users must have the Create CrossLink permission in their security profile and access to at least one other Vault in your domain. Users with the External User license type cannot create CrossLink documents.
## How to Create CrossLinks
You can create CrossLinks in one of three ways:
* By the **Create** drop-down menu
* By converting an existing content placeholder to a CrossLink
* By creating a CrossLink directly in a binder
To create a new CrossLink document using the **Create** menu:
1. Click the arrow on the right side of the **Create** button to view the _Create_ drop-down menu. Select **Document**.
2. From the _Create Document_ menu, select **CrossLink** and click **Continue**.
3. On the **Create CrossLink (Step 1)** page, click **Choose**.
4. In the **Choose Source Documents** dialog, select one or more source documents. One CrossLink is created for each selection. See information about [choosing source documents][2] below.
5. Click **Close**. Selected documents are listed in the **Create CrossLink (Step 2)** page. If you want to CrossLink an existing CrossLink, select the **X** icon beside the _CrossLink: No_ filter to show CrossLinks in the list of selectable documents.
6. Select a document type using the [document type selector](/en/lr/25787/).
7. Click **Next.**
8. Fill in document fields. Fields highlighted in yellow are required. If you're creating multiple CrossLinks, you'll need to [populate fields for each](/en/lr/15445/).
9. In the **Source Document Details** section, Vault defaults the **Source Binding Rule**, but you can update this. See details about [binding rules][5] below.
10. Click **Save** to add the CrossLink to your Library. There may be a short delay before you see the thumbnail and rendition.
## How to Choose Source Documents {#Choose-Source-Docs}
You can add one or more source documents in one or more Vaults in this step. Each selected source document becomes an individual CrossLink. You may select any document, placeholder, or planned document which you have permission to view in all Vaults which you have been assigned access. Binders and unclassified documents cannot be used as source documents for CrossLinks and will not be displayed.
To choose a source document:
1. Use **Source Vault Selector** picklist in the upper-left of the window to choose from other Vaults in the domain.
2. Click into the search field to [search for source documents](/en/lr/442/).
3. Use the **Filters** to apply additional search criteria. Active filters appear above the document list. From there, you can remove them individually or clear all selected filters.
4. Select one or more documents by clicking the green **plus** (**+**) icon for each.
5. Click **Close**. The selected documents appear on the **Create CrossLink** page.
## Source Binding Rules {#crosslinksourcebinding}
CrossLinks can be statically bound to a specific version of the source document or dynamically bound to the latest version or latest steady state version of the source document. In the case of a [CrossLinked CrossLink](/en/lr/23143/#crosslink-crosslink), the CrossLinked CrossLink is not bound to the original document in the primary Vault, and uses the viewable rendition, or the viewable rendition and source file, of the CrossLink in the secondary vault as its source file. Additionally, it is possible that the source binding rule between the primary and secondary Vaults is different from the one between the secondary and tertiary Vaults. Therefore, updates to the document in the primary Vault may or may not propagate to the CrossLinked CrossLink.
### Specific Document Version (Static Binding)
Vault updates the CrossLink document only if a user specifically edits the version of the source document that is bound. It's not possible to modify the viewable rendition on a past version, so your content should not change, but it is possible to edit document fields on a past version, so the Source Document data in your CrossLink document could change.
With this binding rule, Vault will not modify your CrossLink if users create newer versions of the source document.
### Latest Version
The CrossLink is automatically updated with the latest version of the source document (dynamic binding). This includes all workflow state changes: Draft, In Review, In Approval, Approved, etc.
### Latest Steady State Version (Default)
The CrossLink is automatically updated only when the source document reaches a steady state version: Approved, Approved for Use, etc.
When creating a CrossLink with dynamic binding, you may choose any version of the source document. Vault automatically binds the CrossLink to the latest version or latest steady state version.
### Changing Binding Rules
Binding rules cannot be changed from static to dynamic when the CrossLink is in a steady state. To change the binding to dynamic when the CrossLink is in a steady state, you must create a new draft of the CrossLink. The steady state retains the static binding.
To change the binding rules from dynamic to static, you must move the document into a lifecycle state on which your Admin has configured the **Set CrossLink binding to explicit version** entry action.
## Uploading Renditions {#uploading-renditions}
Depending on the CrossLink's document type, you can upload non-viewable renditions to CrossLink documents. If the CrossLink's document type supports additional rendition types, the _Add Rendition_ () button is displayed in the _Rendition_ section of the _Files_ panel on the Doc Info pane, and you can click **Add Rendition** () to manually add a rendition of the configured _Rendition Type_.
Renditions are not synced between the source document and the CrossLink document. Renditions uploaded to a CrossLink document exist independently of the source document, and follow the same permissions and overall process as renditions on a regular, non-CrossLink document. One exception is that the standard viewable, audio, or video rendition type on a CrossLink cannot be removed or altered in any way because it reflects the CrossLink's source document.
## Field Defaulting
To streamline initial data entry when creating a CrossLink, editable field values for the CrossLink are defaulted from the corresponding fields on the source document when the following conditions are met:
* The source document field names and types exactly match those of the CrossLink
* The source document field is active and visible to the user adding the CrossLink. This takes into account field-level security and field dependency rules.
* The CrossLink document field is editable by the user creating the CrossLink, i.e., there are no field overrides or field dependency rules that make the field hidden or read-only.
## Document Lifecycles
CrossLink documents follow their own lifecycles and workflows, not those of the source document. A new lifecycle entry action is available to support specific binding for CrossLinks as part of a lifecycle, e.g., set binding to a specific version. As a best practice, this action should be applied when the CrossLink is moved to a steady state version, to ensure the source content does not continue to change.
## Annotations
One common use for CrossLinks is to create reference documents in one Vault, a PromoMats Vault, for example, that re-uses content from another Vault, such as a Clinical Study Report from eTMF. In this scenario, it is desirable to create anchors in the CrossLink document that can be associated with link annotations in Promotional Pieces or other documents in the CrossLink Vault.
CrossLink documents only allow annotations and anchors if they are statically bound to their source document. Dynamically bound CrossLinks do not allow annotation and if a statically bound CrossLink is switched to dynamic binding, its annotations will be removed.
Also note that the annotations and anchors in source documents are not copied over with the viewable rendition when creating a CrossLink.
## Overlays & Signature Pages
By default, Vault automatically copies over any overlays or signature pages applied to the source document when you create a CrossLink. Depending on your Admin's configuration, your Vault may exclude overlays, signature pages, or both when you create CrossLinks or when they are updated. When you download a CrossLink's viewable rendition, Vault applies any overlays or signature pages defined in the CrossLink document's Vault, not the source document's Vault.
## Archiving Documents
When a user archives a CrossLink document, Vault automatically sets version binding to _Specific Document Version (Static Binding)_ to prevent any further changes to the archived document. Learn more about [document archiving](/en/lr/34126/).
## CrossLink Actions
Most actions on CrossLink documents follow those of regular documents with some exceptions.
The following document actions have CrossLink-specific behavior:
* **Create Draft**: Creates a new minor version of the CrossLink, e.g., 0.1 > 0.2. Users are allowed to increment the CrossLink version only. Learn more about [versioning documents](/en/lr/162/).
* **Resync with Source**: Manually synchronize the CrossLink with its source document.
## Restricted Actions for CrossLinks
Even though a CrossLink is its own document in your Vault and has its own lifecycle, many actions are not available because the content actually exists in another Vault. The following actions are not allowed:
* Make a Copy
* Check Out / Check In
* Upload New Version
* Manage viewable, audio, or video standard renditions
* Archive
[2]: #Choose-Source-Docs
[5]: #crosslinksourcebinding