init data hashing docs

Author: forstisabella

src/privacy/hipaa-eligible-segment.md

@@ -18,4 +18,46 @@ Ensure your Workspace is eligible for HIPAA before you configure and send any pe
 1. In your Workspace, navigate to **Settings > Workspace Settings**.
 2. On the **General Settings** tab, ensure that the HIPAA badge appears. This badge confirms that the Workspace is HIPAA eligible. ![HIPAA Eligible](images/hipaa-eligible.png)
 
-With the BAA signed and Workspace confirmed as eligible, you can start building. For more information about starting a HIPAA compliant implementation, see Twilio's [Architecting for HIPAA on Twilio](https://twil.io/architecting-for-hipaa){:target="_blank"}, which outlines the shared responsibilities and requirements for building and maintaining HIPAA-compliant workflows in Segment.
+With the BAA signed and Workspace confirmed as eligible, you can start building. For more information about starting a HIPAA compliant implementation, see Twilio's [Architecting for HIPAA on Twilio](https://twil.io/architecting-for-hipaa){:target="_blank"}, which outlines the shared responsibilities and requirements for building and maintaining HIPAA-compliant workflows in Segment.
+
+## Data hashing
+
+When workspace owners add new destinations to a HIPAA eligible Segment workspace, they can hash any fields [marked as yellow in the Privacy Portal](/docs/privacy/portal) before data is sent to the destination. 
+
+<!---This feature addresses the Special Considerations for HIPAA section on page 28 of Twilio's [Architecting for HIPAA on Twilio](https://twil.io/architecting-for-hipaa){:target="_blank"} guide.--->
+
+
+### Configure data hashing for a new destination
+
+To configure data hashing while setting up a new destination:
+1. From the Destinations page in the Segment App, click **Add destination**.
+2. Select a destination from the catalog and click **Configure**.
+3. On the Select data source page, select the source you want to connect to your destination.
+4. Click **Next**.
+5. On the Setup page, give your destination a name, fill in any optional settings, and select the **Have Segment hash sensitive data** checkbox.
+6. From the **Fields** dropdown, select one or more fields from which you'd like to hash data and click the **Generate hashing keys** button. 
+7. Copy the Private Key to a secure location - **once you finish setting up the destination, this key cannot be retrieved**. 
+8. Click **Save**.
+
+
+> error "Private Key is not recoverable"
+> Segment does not save the private key created during the data hashing setup flow, and cannot retrieve the key after you finish setting up your destination. You can generate a new key without un-encrypting and re-encrypting your data using the instructions in the [Configure new key pairs](#configure-new-key-pairs) section.
+
+### Configure data hashing for an existing destination
+ 
+To configure data hashing for an existing destination:
+1. Open the [My destinations page](https://app.segment.com/goto-my-workspace/destinations){:target="_blank”} in the Segment app.
+2. Select a destination, and click **Settings**.
+3. On the Settings page, select the **Have Segment hash sensitive data** checkbox.
+4. From the **Fields** dropdown, select one or more fields from which you'd like to hash data and click the **Generate hashing keys** button. 
+5. Copy the Private Key to a secure location - **once you finish configuring data hashing, this key cannot be retrieved**. 
+6. Click **Save**.
+
+
+> error "Private Key is not recoverable"
+> Segment does not save the private key created during the data hashing setup, and cannot retrieve the key after you add data hashing to your destination. You can generate a new key without un-encrypting and re-encrypting your data using the instructions in the [Configure new key pairs](#configure-new-key-pairs) section.
+
+
+### Configure new key pairs
+
+<!---TBD--->