diff --git a/Import.md b/Import.md
index c4d08c5..d235e27 100644
--- a/Import.md
+++ b/Import.md
@@ -210,6 +210,28 @@ mapping:
         replacement: ""
 ```
 
+### deduplication (required)
+
+Currently there's only one deduplication rule type:
+
+#### compare
+
+A `compare` deduplication rule compares the mapped row to a existing transactions.
+
+`compare` can have a `match_type` of `lax`, for case-insensitive comparison or `strict` for case-sensitiveness.
+
+Lastly, use `fields` to name what to compare against (use the target naming).
+
+#### Example
+
+```yaml
+deduplication:
+  - type: compare
+    fields:
+      - internal_id
+      - name
+    match_type: strict
+```
 
 ## New versions