diff --git a/dexlib2/src/main/java/org/jf/dexlib2/builder/BuilderDebugItem.java b/dexlib2/src/main/java/org/jf/dexlib2/builder/BuilderDebugItem.java
new file mode 100644
index 00000000..702121f9
--- /dev/null
+++ b/dexlib2/src/main/java/org/jf/dexlib2/builder/BuilderDebugItem.java
@@ -0,0 +1,26 @@
+package org.jf.dexlib2.builder;
+
+import org.jf.dexlib2.DebugItemType;
+import org.jf.dexlib2.iface.debug.*;
+import org.jf.dexlib2.iface.reference.StringReference;
+import org.jf.dexlib2.iface.reference.TypeReference;
+
+import javax.annotation.Nonnull;
+import javax.annotation.Nullable;
+
+public abstract class BuilderDebugItem implements DebugItem {
+    @Nullable MethodLocation location;
+
+    public BuilderDebugItem(@Nonnull MethodLocation location) {
+        this.location = location;
+    }
+
+    @Override public int getCodeAddress() {
+        if (location == null) {
+            throw new IllegalStateException("Cannot get the address of a BuilderDebugItem that isn't associated with " +
+                    "a method.");
+        }
+        return location.getCodeAddress();
+    }
+
+}
diff --git a/dexlib2/src/main/java/org/jf/dexlib2/builder/MethodImplementationBuilder.java b/dexlib2/src/main/java/org/jf/dexlib2/builder/MethodImplementationBuilder.java
index db21fab7..5508977a 100644
--- a/dexlib2/src/main/java/org/jf/dexlib2/builder/MethodImplementationBuilder.java
+++ b/dexlib2/src/main/java/org/jf/dexlib2/builder/MethodImplementationBuilder.java
@@ -41,7 +41,7 @@ public class MethodImplementationBuilder<ReferenceType extends Reference> {
             if (label.isPlaced()) {
                 throw new IllegalArgumentException("There is already a label with that name.");
             } else {
-                currentLocation.addLabel(label);
+                currentLocation.getLabels().add(label);
             }
         } else {
             label = currentLocation.addNewLabel();
@@ -86,25 +86,32 @@ public class MethodImplementationBuilder<ReferenceType extends Reference> {
     }
 
     public void addLineNumber(int lineNumber) {
+        currentLocation.addLineNumber(lineNumber);
     }
 
     public void addStartLocal(int registerNumber, @Nullable StringReference name, @Nullable TypeReference type,
                               @Nullable StringReference signature) {
+        currentLocation.addStartLocal(registerNumber, name, type, signature);
     }
 
     public void addEndLocal(int registerNumber) {
+        currentLocation.addEndLocal(registerNumber);
     }
 
     public void addRestartLocal(int registerNumber) {
+        currentLocation.addRestartLocal(registerNumber);
     }
 
     public void addPrologue() {
+        currentLocation.addPrologue();
     }
 
     public void addEpilogue() {
+        currentLocation.addEpilogue();
     }
 
     public void addSetSourceFile(@Nullable BuilderStringReference sourceFile) {
+        currentLocation.addSetSourceFile(sourceFile);
     }
 
     public void addInstruction10t(@Nonnull Opcode opcode,
diff --git a/dexlib2/src/main/java/org/jf/dexlib2/builder/MethodLocation.java b/dexlib2/src/main/java/org/jf/dexlib2/builder/MethodLocation.java
index 97b6b1e9..700a8157 100644
--- a/dexlib2/src/main/java/org/jf/dexlib2/builder/MethodLocation.java
+++ b/dexlib2/src/main/java/org/jf/dexlib2/builder/MethodLocation.java
@@ -1,13 +1,15 @@
 package org.jf.dexlib2.builder;
 
 import com.google.common.collect.Lists;
+import org.jf.dexlib2.builder.debug.*;
 import org.jf.dexlib2.iface.instruction.Instruction;
+import org.jf.dexlib2.iface.reference.StringReference;
+import org.jf.dexlib2.iface.reference.TypeReference;
+import org.jf.dexlib2.writer.builder.BuilderStringReference;
 
 import javax.annotation.Nonnull;
 import javax.annotation.Nullable;
-import java.util.Collection;
-import java.util.Collections;
-import java.util.List;
+import java.util.*;
 
 public class MethodLocation {
     @Nullable Instruction instruction;
@@ -15,6 +17,7 @@ public class MethodLocation {
     int index;
 
     private List<Label> labels = Lists.newArrayList();
+    List<BuilderDebugItem> debugItems = Lists.newArrayList();
 
     MethodLocation(@Nullable Instruction instruction,
     int codeAddress, int index) {
@@ -37,16 +40,47 @@ public class MethodLocation {
     }
 
     @Nonnull
-    public Collection<Label> getLabels() {
-        return Collections.unmodifiableCollection(labels);
-    }
+    public Set<Label> getLabels() {
+        return new AbstractSet<Label>() {
+            @Nonnull
+            @Override public Iterator<Label> iterator() {
+                final Iterator<Label> it = labels.iterator();
 
-    public void addLabel(@Nonnull Label label) {
-        if (label.isPlaced()) {
-            label.getLocation().removeLabel(label);
-        }
-        label.location = this;
-        labels.add(label);
+                return new Iterator<Label>() {
+                    private @Nullable Label currentLabel = null;
+
+                    @Override public boolean hasNext() {
+                        return it.hasNext();
+                    }
+
+                    @Override public Label next() {
+                        currentLabel = it.next();
+                        return currentLabel;
+                    }
+
+                    @Override public void remove() {
+                        if (currentLabel != null) {
+                            currentLabel.location = null;
+                        }
+                        it.remove();
+                    }
+                };
+            }
+
+            @Override public int size() {
+                return labels.size();
+            }
+
+            @Override public boolean add(@Nonnull Label label) {
+                if (label.isPlaced()) {
+                    throw new IllegalArgumentException("Cannot add a label that is already placed. You must remove " +
+                            "it from its current location first.");
+                }
+                label.location = MethodLocation.this;
+                labels.add(label);
+                return true;
+            }
+        };
     }
 
     @Nonnull
@@ -56,10 +90,76 @@ public class MethodLocation {
         return label;
     }
 
-    public void removeLabel(@Nonnull Label label) {
-        for (int i=0; i<labels.size(); i++) {
-            labels.remove(label);
-        }
-        label.location = null;
+    @Nonnull
+    public Set<BuilderDebugItem> getDebugItems() {
+        return new AbstractSet<BuilderDebugItem>() {
+            @Nonnull
+            @Override public Iterator<BuilderDebugItem> iterator() {
+                final Iterator<BuilderDebugItem> it = debugItems.iterator();
+
+                return new Iterator<BuilderDebugItem>() {
+                    private @Nullable BuilderDebugItem currentDebugItem = null;
+
+                    @Override public boolean hasNext() {
+                        return it.hasNext();
+                    }
+
+                    @Override public BuilderDebugItem next() {
+                        currentDebugItem = it.next();
+                        return currentDebugItem;
+                    }
+
+                    @Override public void remove() {
+                        if (currentDebugItem != null) {
+                            currentDebugItem.location = null;
+                        }
+                        it.remove();
+                    }
+                };
+            }
+
+            @Override public int size() {
+                return labels.size();
+            }
+
+            @Override public boolean add(@Nonnull BuilderDebugItem debugItem) {
+                if (debugItem.location != null) {
+                    throw new IllegalArgumentException("Cannot add a debug item that has already been added to a " +
+                            "method. You must remove it from its current location first.");
+                }
+                debugItem.location = MethodLocation.this;
+                debugItems.add(debugItem);
+                return true;
+            }
+        };
+    }
+
+    public void addLineNumber(int lineNumber) {
+        debugItems.add(new BuilderLineNumber(this, lineNumber));
+    }
+
+    public void addStartLocal(int registerNumber, @Nullable StringReference name, @Nullable TypeReference type,
+                              @Nullable StringReference signature) {
+        debugItems.add(new BuilderStartLocal(this, registerNumber, name, type, signature));
+    }
+
+    public void addEndLocal(int registerNumber) {
+        debugItems.add(new BuilderEndLocal(this, registerNumber));
+    }
+
+    public void addRestartLocal(int registerNumber) {
+        debugItems.add(new BuilderRestartLocal(this, registerNumber));
+    }
+
+    public void addPrologue() {
+        debugItems.add(new BuilderPrologueEnd(this));
+    }
+
+    public void addEpilogue() {
+        debugItems.add(new BuilderEpilogueBegin(this));
+    }
+
+    public void addSetSourceFile(@Nullable BuilderStringReference sourceFile) {
+        debugItems.add(new BuilderSetSourceFile(this, sourceFile));
     }
 }
diff --git a/dexlib2/src/main/java/org/jf/dexlib2/builder/debug/BuilderEndLocal.java b/dexlib2/src/main/java/org/jf/dexlib2/builder/debug/BuilderEndLocal.java
new file mode 100644
index 00000000..5b69c9ab
--- /dev/null
+++ b/dexlib2/src/main/java/org/jf/dexlib2/builder/debug/BuilderEndLocal.java
@@ -0,0 +1,26 @@
+package org.jf.dexlib2.builder.debug;
+
+import org.jf.dexlib2.DebugItemType;
+import org.jf.dexlib2.builder.BuilderDebugItem;
+import org.jf.dexlib2.builder.MethodLocation;
+import org.jf.dexlib2.iface.debug.EndLocal;
+
+import javax.annotation.Nonnull;
+import javax.annotation.Nullable;
+
+public class BuilderEndLocal extends BuilderDebugItem implements EndLocal {
+    private final int register;
+
+    public BuilderEndLocal(@Nonnull MethodLocation location,
+                           int register) {
+        super(location);
+        this.register = register;
+    }
+
+    @Override public int getRegister() { return register; }
+    @Nullable @Override public String getName() { return null; }
+    @Nullable @Override public String getType() { return null; }
+    @Nullable @Override public String getSignature() { return null; }
+
+    @Override public int getDebugItemType() { return DebugItemType.END_LOCAL; }
+}
diff --git a/dexlib2/src/main/java/org/jf/dexlib2/builder/debug/BuilderEpilogueBegin.java b/dexlib2/src/main/java/org/jf/dexlib2/builder/debug/BuilderEpilogueBegin.java
new file mode 100644
index 00000000..cea37e66
--- /dev/null
+++ b/dexlib2/src/main/java/org/jf/dexlib2/builder/debug/BuilderEpilogueBegin.java
@@ -0,0 +1,16 @@
+package org.jf.dexlib2.builder.debug;
+
+import org.jf.dexlib2.DebugItemType;
+import org.jf.dexlib2.builder.BuilderDebugItem;
+import org.jf.dexlib2.builder.MethodLocation;
+import org.jf.dexlib2.iface.debug.EpilogueBegin;
+
+import javax.annotation.Nonnull;
+
+public class BuilderEpilogueBegin extends BuilderDebugItem implements EpilogueBegin {
+    public BuilderEpilogueBegin(@Nonnull MethodLocation location) {
+        super(location);
+    }
+
+    @Override public int getDebugItemType() { return DebugItemType.EPILOGUE_BEGIN; }
+}
diff --git a/dexlib2/src/main/java/org/jf/dexlib2/builder/debug/BuilderLineNumber.java b/dexlib2/src/main/java/org/jf/dexlib2/builder/debug/BuilderLineNumber.java
new file mode 100644
index 00000000..d82811f0
--- /dev/null
+++ b/dexlib2/src/main/java/org/jf/dexlib2/builder/debug/BuilderLineNumber.java
@@ -0,0 +1,22 @@
+package org.jf.dexlib2.builder.debug;
+
+import org.jf.dexlib2.DebugItemType;
+import org.jf.dexlib2.builder.BuilderDebugItem;
+import org.jf.dexlib2.builder.MethodLocation;
+import org.jf.dexlib2.iface.debug.LineNumber;
+
+import javax.annotation.Nonnull;
+
+public class BuilderLineNumber extends BuilderDebugItem implements LineNumber {
+    private final int lineNumber;
+
+    public BuilderLineNumber(@Nonnull MethodLocation location,
+                             int lineNumber) {
+        super(location);
+        this.lineNumber = lineNumber;
+    }
+
+    @Override public int getLineNumber() { return lineNumber; }
+
+    @Override public int getDebugItemType() { return DebugItemType.LINE_NUMBER; }
+}
diff --git a/dexlib2/src/main/java/org/jf/dexlib2/builder/debug/BuilderPrologueEnd.java b/dexlib2/src/main/java/org/jf/dexlib2/builder/debug/BuilderPrologueEnd.java
new file mode 100644
index 00000000..879db476
--- /dev/null
+++ b/dexlib2/src/main/java/org/jf/dexlib2/builder/debug/BuilderPrologueEnd.java
@@ -0,0 +1,16 @@
+package org.jf.dexlib2.builder.debug;
+
+import org.jf.dexlib2.DebugItemType;
+import org.jf.dexlib2.builder.BuilderDebugItem;
+import org.jf.dexlib2.builder.MethodLocation;
+import org.jf.dexlib2.iface.debug.PrologueEnd;
+
+import javax.annotation.Nonnull;
+
+public class BuilderPrologueEnd extends BuilderDebugItem implements PrologueEnd {
+    public BuilderPrologueEnd(@Nonnull MethodLocation location) {
+        super(location);
+    }
+
+    @Override public int getDebugItemType() { return DebugItemType.PROLOGUE_END; }
+}
diff --git a/dexlib2/src/main/java/org/jf/dexlib2/builder/debug/BuilderRestartLocal.java b/dexlib2/src/main/java/org/jf/dexlib2/builder/debug/BuilderRestartLocal.java
new file mode 100644
index 00000000..65c39641
--- /dev/null
+++ b/dexlib2/src/main/java/org/jf/dexlib2/builder/debug/BuilderRestartLocal.java
@@ -0,0 +1,26 @@
+package org.jf.dexlib2.builder.debug;
+
+import org.jf.dexlib2.DebugItemType;
+import org.jf.dexlib2.builder.BuilderDebugItem;
+import org.jf.dexlib2.builder.MethodLocation;
+import org.jf.dexlib2.iface.debug.RestartLocal;
+
+import javax.annotation.Nonnull;
+import javax.annotation.Nullable;
+
+public class BuilderRestartLocal extends BuilderDebugItem implements RestartLocal {
+    private final int register;
+
+    public BuilderRestartLocal(@Nonnull MethodLocation location,
+                               int register) {
+        super(location);
+        this.register = register;
+    }
+
+    @Override public int getRegister() { return register; }
+    @Nullable @Override public String getName() { return null; }
+    @Nullable @Override public String getType() { return null; }
+    @Nullable @Override public String getSignature() { return null; }
+
+    @Override public int getDebugItemType() { return DebugItemType.RESTART_LOCAL; }
+}
diff --git a/dexlib2/src/main/java/org/jf/dexlib2/builder/debug/BuilderSetSourceFile.java b/dexlib2/src/main/java/org/jf/dexlib2/builder/debug/BuilderSetSourceFile.java
new file mode 100644
index 00000000..58223db8
--- /dev/null
+++ b/dexlib2/src/main/java/org/jf/dexlib2/builder/debug/BuilderSetSourceFile.java
@@ -0,0 +1,31 @@
+package org.jf.dexlib2.builder.debug;
+
+import org.jf.dexlib2.DebugItemType;
+import org.jf.dexlib2.builder.BuilderDebugItem;
+import org.jf.dexlib2.builder.MethodLocation;
+import org.jf.dexlib2.iface.debug.SetSourceFile;
+import org.jf.dexlib2.iface.reference.StringReference;
+
+import javax.annotation.Nonnull;
+import javax.annotation.Nullable;
+
+public class BuilderSetSourceFile extends BuilderDebugItem implements SetSourceFile {
+    @Nullable
+    private final StringReference sourceFile;
+
+    public BuilderSetSourceFile(@Nonnull MethodLocation location,
+                                @Nullable StringReference sourceFile) {
+        super(location);
+        this.sourceFile = sourceFile;
+    }
+
+    @Override public int getDebugItemType() { return DebugItemType.SET_SOURCE_FILE; }
+
+    @Nullable @Override public String getSourceFile() {
+        return sourceFile==null?null:sourceFile.getString();
+    }
+
+    @Nullable @Override public StringReference getSourceFileReference() {
+        return sourceFile;
+    }
+}
diff --git a/dexlib2/src/main/java/org/jf/dexlib2/builder/debug/BuilderStartLocal.java b/dexlib2/src/main/java/org/jf/dexlib2/builder/debug/BuilderStartLocal.java
new file mode 100644
index 00000000..c9f05e23
--- /dev/null
+++ b/dexlib2/src/main/java/org/jf/dexlib2/builder/debug/BuilderStartLocal.java
@@ -0,0 +1,50 @@
+package org.jf.dexlib2.builder.debug;
+
+import org.jf.dexlib2.DebugItemType;
+import org.jf.dexlib2.builder.BuilderDebugItem;
+import org.jf.dexlib2.builder.MethodLocation;
+import org.jf.dexlib2.iface.debug.StartLocal;
+import org.jf.dexlib2.iface.reference.StringReference;
+import org.jf.dexlib2.iface.reference.TypeReference;
+
+import javax.annotation.Nonnull;
+import javax.annotation.Nullable;
+
+public class BuilderStartLocal extends BuilderDebugItem implements StartLocal {
+    private final int register;
+    @Nullable private final StringReference name;
+    @Nullable private final TypeReference type;
+    @Nullable private final StringReference signature;
+
+    public BuilderStartLocal(@Nonnull MethodLocation location,
+                             int register,
+                             @Nullable StringReference name,
+                             @Nullable TypeReference type,
+                             @Nullable StringReference signature) {
+        super(location);
+        this.register = register;
+        this.name = name;
+        this.type = type;
+        this.signature = signature;
+    }
+
+    @Override public int getRegister() { return register; }
+
+    @Nullable @Override public StringReference getNameReference() { return name; }
+    @Nullable @Override public TypeReference getTypeReference() { return type; }
+    @Nullable @Override public StringReference getSignatureReference() { return signature; }
+
+    @Nullable @Override public String getName() {
+        return name==null?null:name.getString();
+    }
+
+    @Nullable @Override public String getType() {
+        return type==null?null:type.getType();
+    }
+
+    @Nullable @Override public String getSignature() {
+        return signature==null?null:signature.getString();
+    }
+
+    @Override public int getDebugItemType() { return DebugItemType.START_LOCAL; }
+}