diff --git a/docs/UserGuide.md b/docs/UserGuide.md
index ff0bb22b067..ae5be7748d8 100644
--- a/docs/UserGuide.md
+++ b/docs/UserGuide.md
@@ -189,6 +189,20 @@ Examples:
 * `remark 1 r/Financial Issues` Adds the remark of the 1st person to be `Financial Issues`.
 * `remark 1 r/` Clears remarks (if any) of the 1st person.
 
+### Sorting the person list : `sort`
+
+Sorts the list of persons being viewed by name or date of last visit in ascending or descending order.
+
+Format: `sort parameter/order`
+
+* Sorts the displayed list of persons according to the specified order.
+* Order can be specified as ascending by leaving the order blank or **asc**/**ascending**
+* Order can be specified as descending by **descending**/**desc**
+
+Examples:
+* `sort n/` sorts by name in ascending order.
+* `sort d/descending` sorts by date of last visit in descending order.
+
 ### Clearing all entries : `clear`
 
 Clears all entries from the address book.
@@ -255,4 +269,5 @@ Action     | Format, Examples
 **View**   | `view INDEX`<br> e.g.,`view 1`
 **Help**   | `help`
 **Seed**   | `seed`
+**Sort**   | `sort parameter/order` <br> e.g., `sort n/ascending`
 **Remark** | `remark INDEX r/REMARK`
diff --git a/docs/diagrams/ModelClassDiagram.puml b/docs/diagrams/ModelClassDiagram.puml
index 6a1538263ed..e9a5100e9ee 100644
--- a/docs/diagrams/ModelClassDiagram.puml
+++ b/docs/diagrams/ModelClassDiagram.puml
@@ -13,6 +13,7 @@ Class ModelManager
 Class UserPrefs
 
 Class UniquePersonList
+Class PersonComparator
 Class Person
 Class Address
 Class Email
@@ -39,6 +40,7 @@ ModelManager -right-> "1" UserPrefs
 UserPrefs .up.|> ReadOnlyUserPrefs
 
 AddressBook *--> "1" UniquePersonList
+UniquePersonList .left.> PersonComparator
 UniquePersonList --> "~* all" Person
 Person *--> Name
 Person *--> Phone
@@ -47,7 +49,7 @@ Person *--> Address
 Person *--> "*" Tag
 Person *--> EmergencyContact
 Person *--> DateOfLastVisit
-Person *--> Remark
+Person *--> "1" Remark
 
 Person -[hidden]up--> I
 UniquePersonList -[hidden]right-> I