diff --git a/src/main/java/me/mrletsplay/shareclientcore/document/ArrayCharBag.java b/src/main/java/me/mrletsplay/shareclientcore/document/ArrayCharBag.java
index 9dd8a63..b095b50 100644
--- a/src/main/java/me/mrletsplay/shareclientcore/document/ArrayCharBag.java
+++ b/src/main/java/me/mrletsplay/shareclientcore/document/ArrayCharBag.java
@@ -12,6 +12,7 @@ public class ArrayCharBag implements CharBag {
 		int i = 0;
 		// TODO: use binary search
 		while(i < chars.size() && Util.comparePositions(chars.get(i).position(), character.position()) < 0) i++;
+		if(i < chars.size() && Util.comparePositions(chars.get(i).position(), character.position()) == 0) return -1;
 		chars.add(i, character);
 		return i;
 	}
diff --git a/src/main/java/me/mrletsplay/shareclientcore/document/CharBag.java b/src/main/java/me/mrletsplay/shareclientcore/document/CharBag.java
index 4be6f88..642f925 100644
--- a/src/main/java/me/mrletsplay/shareclientcore/document/CharBag.java
+++ b/src/main/java/me/mrletsplay/shareclientcore/document/CharBag.java
@@ -2,12 +2,8 @@ package me.mrletsplay.shareclientcore.document;
 
 public interface CharBag {
 
-//	public Character find(PositionIdentifier position);
-//	public Character findBefore(PositionIdentifier position);
-//	public Character findAfter(PositionIdentifier position);
-
 	/**
-	 * Adds a character to the bag and returns the index it was inserted at
+	 * Adds a character to the bag and returns the index it was inserted at, or -1 if it was not inserted because it already exists
 	 * @param character The character to add
 	 * @return The index it was inserted at
 	 */
diff --git a/src/main/java/me/mrletsplay/shareclientcore/document/Document.java b/src/main/java/me/mrletsplay/shareclientcore/document/Document.java
index 77c882d..2e1016e 100644
--- a/src/main/java/me/mrletsplay/shareclientcore/document/Document.java
+++ b/src/main/java/me/mrletsplay/shareclientcore/document/Document.java
@@ -48,6 +48,26 @@ public class Document {
 		}
 	}
 
+	/**
+	 * Inserts a remote change into the document and updates internal parameters accordingly
+	 * @param c The character to insert
+	 * @return The index of the inserted character, or -1 if it was not inserted because it already exists
+	 */
+	public int remoteInsert(Char c) {
+		lamport = Math.max(c.lamport(), lamport) + 1;
+		return charBag.add(c);
+	}
+
+	/**
+	 * Removes a character from the document and updates internal parameters accordingly
+	 * @param c The character to delete
+	 * @return The index the character was located at, or -1 if it was not contained in the document
+	 */
+	public int remoteDelete(Char c) {
+		lamport = Math.max(c.lamport(), lamport) + 1;
+		return charBag.remove(c);
+	}
+
 	public CharBag getCharBag() {
 		return charBag;
 	}