diff --git a/conversation.go b/conversation.go
index e523716cc..a5eed4ff8 100644
--- a/conversation.go
+++ b/conversation.go
@@ -398,13 +398,14 @@ func (api *Client) LeaveConversationContext(ctx context.Context, channelID strin
 }
 
 type GetConversationRepliesParameters struct {
-	ChannelID string
-	Timestamp string
-	Cursor    string
-	Inclusive bool
-	Latest    string
-	Limit     int
-	Oldest    string
+	ChannelID          string
+	Timestamp          string
+	Cursor             string
+	Inclusive          bool
+	Latest             string
+	Limit              int
+	Oldest             string
+	IncludeAllMetadata bool
 }
 
 // GetConversationReplies retrieves a thread of messages posted to a conversation
@@ -436,6 +437,11 @@ func (api *Client) GetConversationRepliesContext(ctx context.Context, params *Ge
 	} else {
 		values.Add("inclusive", "0")
 	}
+	if params.IncludeAllMetadata {
+		values.Add("include_all_metadata", "1")
+	} else {
+		values.Add("include_all_metadata", "0")
+	}
 	response := struct {
 		SlackResponse
 		HasMore          bool `json:"has_more"`