diff --git a/SourceGen/DefSymbol.cs b/SourceGen/DefSymbol.cs
index 1e4f20b..b166e8a 100644
--- a/SourceGen/DefSymbol.cs
+++ b/SourceGen/DefSymbol.cs
@@ -23,6 +23,8 @@ namespace SourceGen {
     /// Instances are immutable.
     /// </summary>
     public class DefSymbol : Symbol {
+        public const int NO_WIDTH = -1;
+
         /// <summary>
         /// Data format descriptor.
         /// </summary>
@@ -40,8 +42,9 @@ namespace SourceGen {
         public string Tag { get; private set; }
 
         /// <summary>
-        /// Number of bytes referenced by the symbol.  Useful for identifying two-byte and
-        /// three-byte pointers.  Used for Variables.
+        /// Number of bytes referenced by the symbol.  Useful for identifying multi-byte items,
+        /// such as two-byte and three-byte pointers.  Used for Variables.  Value will be
+        /// NO_WIDTH if unset.
         /// </summary>
         public int Width { get; private set; }
 
@@ -62,6 +65,7 @@ namespace SourceGen {
             Debug.Assert(source == Source.Platform || source == Source.Project);
             Debug.Assert(type == Type.ExternalAddr || type == Type.Constant);
             Xrefs = new XrefSet();
+            Width = NO_WIDTH;
         }
 
         /// <summary>
diff --git a/SourceGen/LineListGen.cs b/SourceGen/LineListGen.cs
index d634543..33d51c6 100644
--- a/SourceGen/LineListGen.cs
+++ b/SourceGen/LineListGen.cs
@@ -1069,6 +1069,8 @@ namespace SourceGen {
                 // isn't the ORG at the start of the file.  (This may temporarily do
                 // double-spacing if we do a partial update, because we won't be able to
                 // "see" the previous line.  Harmless.)
+                // TODO: consider always adding blanks, and doing a fix-up pass afterward.
+                //       (but keep in mind that blank lines should always come above things)
                 //
                 // Interesting case:
                 //   .dd2 $1000
diff --git a/SourceGen/LocalVariableTable.cs b/SourceGen/LocalVariableTable.cs
new file mode 100644
index 0000000..99e8d23
--- /dev/null
+++ b/SourceGen/LocalVariableTable.cs
@@ -0,0 +1,64 @@
+/*
+ * Copyright 2019 faddenSoft
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+using System;
+using System.Collections.Generic;
+
+namespace SourceGen {
+    /// <summary>
+    /// Table of redefinable variables.  A project may have several of these, at different
+    /// offsets.  The contents of later tables overwrite the contents of earlier tables.
+    /// </summary>
+    public class LocalVariableTable {
+        /// <summary>
+        /// List of variables.  The symbol's label must be unique within a table, so we sort
+        /// on that.
+        /// </summary>
+        private SortedList<string, DefSymbol> mVariables;
+
+        /// <summary>
+        /// If set, all values from previous VariableTables should be discarded when this
+        /// table is encountered.
+        /// </summary>
+        /// <remarks>
+        /// Might be useful to allow addresses (DP ops) and constants (StackRel ops) to be
+        /// cleared independently, but I suspect the typical compiled-language scenario will
+        /// involve StackRel for args and a sliding DP for locals, so generally it makes
+        /// sense to just clear both.
+        /// </remarks>
+        public bool ClearPrevious { get; set; }
+
+        /// <summary>
+        /// Indexer.
+        /// </summary>
+        /// <param name="key">Symbol's label.</param>
+        /// <returns>Matching symbol.  Throws an exception if not found.</returns>
+        public DefSymbol this[string key] {
+            get {
+                return mVariables[key];
+            }
+            set {
+                mVariables[key] = value;
+            }
+        }
+
+        /// <summary>
+        /// Constructs an empty table.
+        /// </summary>
+        public LocalVariableTable() {
+            mVariables = new SortedList<string, DefSymbol>();
+        }
+    }
+}
diff --git a/SourceGen/MainController.cs b/SourceGen/MainController.cs
index 549faec..ef592c9 100644
--- a/SourceGen/MainController.cs
+++ b/SourceGen/MainController.cs
@@ -1685,6 +1685,18 @@ namespace SourceGen {
             }
         }
 
+        public bool CanEditLocalVariableTable() {
+            return true;        // TODO
+        }
+
+        public void EditLocalVariableTable() {
+            // TODO
+            EditLocalVariableTable dlg = new EditLocalVariableTable(mMainWin);
+            if (dlg.ShowDialog() != true) {
+                return;
+            }
+        }
+
         public bool CanEditLongComment() {
             if (SelectionAnalysis.mNumItemsSelected != 1) {
                 return false;
diff --git a/SourceGen/SourceGen.csproj b/SourceGen/SourceGen.csproj
index de56815..58d38d9 100644
--- a/SourceGen/SourceGen.csproj
+++ b/SourceGen/SourceGen.csproj
@@ -89,6 +89,7 @@
     <Compile Include="Tools\WpfGui\ShowText.xaml.cs">
       <DependentUpon>ShowText.xaml</DependentUpon>
     </Compile>
+    <Compile Include="LocalVariableTable.cs" />
     <Compile Include="WpfGui\AboutBox.xaml.cs">
       <DependentUpon>AboutBox.xaml</DependentUpon>
     </Compile>
@@ -110,6 +111,9 @@
     <Compile Include="WpfGui\EditLabel.xaml.cs">
       <DependentUpon>EditLabel.xaml</DependentUpon>
     </Compile>
+    <Compile Include="WpfGui\EditLocalVariableTable.xaml.cs">
+      <DependentUpon>EditLocalVariableTable.xaml</DependentUpon>
+    </Compile>
     <Compile Include="WpfGui\EditLongComment.xaml.cs">
       <DependentUpon>EditLongComment.xaml</DependentUpon>
     </Compile>
@@ -262,6 +266,10 @@
       <SubType>Designer</SubType>
       <Generator>MSBuild:Compile</Generator>
     </Page>
+    <Page Include="WpfGui\EditLocalVariableTable.xaml">
+      <SubType>Designer</SubType>
+      <Generator>MSBuild:Compile</Generator>
+    </Page>
     <Page Include="WpfGui\EditLongComment.xaml">
       <SubType>Designer</SubType>
       <Generator>MSBuild:Compile</Generator>
diff --git a/SourceGen/WpfGui/EditLocalVariableTable.xaml b/SourceGen/WpfGui/EditLocalVariableTable.xaml
new file mode 100644
index 0000000..e49a31a
--- /dev/null
+++ b/SourceGen/WpfGui/EditLocalVariableTable.xaml
@@ -0,0 +1,85 @@
+<!--
+Copyright 2019 faddenSoft
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+-->
+
+<Window x:Class="SourceGen.WpfGui.EditLocalVariableTable"
+        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
+        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+        xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
+        xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
+        xmlns:local="clr-namespace:SourceGen.WpfGui"
+        mc:Ignorable="d"
+        Title="Edit Local Variable Table"
+        SizeToContent="WidthAndHeight" ResizeMode="NoResize"
+        ShowInTaskbar="False" WindowStartupLocation="CenterOwner"
+        Loaded="Window_Loaded">
+    <Grid Margin="8">
+        <Grid.ColumnDefinitions>
+            <ColumnDefinition Width="*"/>
+            <ColumnDefinition Width="Auto"/>
+        </Grid.ColumnDefinitions>
+        <Grid.RowDefinitions>
+            <RowDefinition Height="Auto"/>
+            <RowDefinition Height="*"/>
+            <RowDefinition Height="Auto"/>
+            <RowDefinition Height="Auto"/>
+        </Grid.RowDefinitions>
+
+        <TextBlock Grid.Column="0" Grid.Row="0" Grid.ColumnSpan="2"
+                   Margin="0,4,0,0" Text="Symbols defined in project:"/>
+
+        <ListView Name="symbolsListView" Grid.Column="0" Grid.Row="1" Margin="0,4,4,0"
+                  Height="300"
+                  FontFamily="{StaticResource GeneralMonoFont}"
+                  ItemsSource="{Binding Variables}"
+                  SnapsToDevicePixels="True" SelectionMode="Single"
+                  SelectionChanged="SymbolsListView_SelectionChanged"
+                  MouseDoubleClick="SymbolsListView_MouseDoubleClick">
+            <ListView.Resources>
+                <Style TargetType="TextBlock">
+                    <Setter Property="TextTrimming" Value="CharacterEllipsis"/>
+                </Style>
+            </ListView.Resources>
+            <ListView.View>
+                <GridView AllowsColumnReorder="False">
+                    <GridViewColumn Header="Name" Width="118" DisplayMemberBinding="{Binding Label}"/>
+                    <GridViewColumn Header="Value" Width="72" DisplayMemberBinding="{Binding Value}"/>
+                    <GridViewColumn Header="Type" Width="45" DisplayMemberBinding="{Binding Type}"/>
+                    <GridViewColumn Header="Width" Width="45" DisplayMemberBinding="{Binding Width}"/>
+                    <GridViewColumn Header="Comment" Width="300" DisplayMemberBinding="{Binding Comment}"/>
+                </GridView>
+            </ListView.View>
+        </ListView>
+
+        <StackPanel Grid.Column="1" Grid.Row="1">
+            <Button Name="newSymbolButton" Width="120" Margin="4" Content="_New Symbol..."
+                    Click="NewSymbolButton_Click"/>
+            <Button Name="editSymbolButton" Width="120" Margin="4,4" Content="_Edit Symbol..."
+                    Click="EditSymbolButton_Click"/>
+            <Button Name="removeSymbolButton" Width="120" Margin="4,4" Content="_Remove"
+                    Click="RemoveSymbolButton_Click"/>
+        </StackPanel>
+
+        <CheckBox Grid.Column="0" Grid.Row="2" Margin="0,4" Click="DeleteTableButton_Click"
+                  Content="Clear values from previous tables"/>
+
+        <DockPanel Grid.Column="0" Grid.Row="3" Grid.ColumnSpan="2" Margin="0,8,0,0" LastChildFill="False">
+            <Button DockPanel.Dock="Left" Content="Delete Table" Width="120"/>
+            <Button DockPanel.Dock="Right" Content="Cancel" Width="70" Margin="8,0,0,0" IsCancel="True"/>
+            <Button DockPanel.Dock="Right" Grid.Column="1" Content="OK" Width="70"
+                    IsDefault="True" Click="OkButton_Click"/>
+        </DockPanel>
+    </Grid>
+</Window>
diff --git a/SourceGen/WpfGui/EditLocalVariableTable.xaml.cs b/SourceGen/WpfGui/EditLocalVariableTable.xaml.cs
new file mode 100644
index 0000000..ba0c8ea
--- /dev/null
+++ b/SourceGen/WpfGui/EditLocalVariableTable.xaml.cs
@@ -0,0 +1,83 @@
+/*
+ * Copyright 2019 faddenSoft
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+using System;
+using System.Collections.Generic;
+using System.Collections.ObjectModel;
+using System.ComponentModel;
+using System.Diagnostics;
+using System.Runtime.CompilerServices;
+using System.Windows;
+using System.Windows.Controls;
+using System.Windows.Input;
+using System.Windows.Media;
+
+namespace SourceGen.WpfGui {
+    /// <summary>
+    /// Edit a LocalVariableTable.
+    /// </summary>
+    public partial class EditLocalVariableTable : Window {
+        // Item for the symbol list view.
+        public class FormattedSymbol {
+            public string Label { get; private set; }
+            public string Value { get; private set; }
+            public string Type { get; private set; }
+            public string Width { get; private set; }
+            public string Comment { get; private set; }
+
+            public FormattedSymbol(string label, string value, string type, string width,
+                    string comment) {
+                Label = label;
+                Value = value;
+                Type = type;
+                Width = width;
+                Comment = comment;
+            }
+        }
+        public ObservableCollection<FormattedSymbol> Variables { get; private set; } =
+            new ObservableCollection<FormattedSymbol>();
+
+        public EditLocalVariableTable(Window owner) {
+            InitializeComponent();
+            Owner = owner;
+            DataContext = this;
+        }
+
+        public void Window_Loaded(object sender, RoutedEventArgs e) {
+        }
+
+        private void OkButton_Click(object sender, RoutedEventArgs e) {
+            DialogResult = true;
+        }
+
+        private void DeleteTableButton_Click(object sender, RoutedEventArgs e) {
+        }
+
+        private void SymbolsListView_SelectionChanged(object sender, SelectionChangedEventArgs e) {
+        }
+
+        private void SymbolsListView_MouseDoubleClick(object sender, MouseButtonEventArgs e) {
+        }
+
+        private void NewSymbolButton_Click(object sender, RoutedEventArgs e) {
+        }
+
+        private void EditSymbolButton_Click(object sender, EventArgs e) {
+        }
+
+        private void RemoveSymbolButton_Click(object sender, RoutedEventArgs e) {
+        }
+    }
+}
diff --git a/SourceGen/WpfGui/MainWindow.xaml b/SourceGen/WpfGui/MainWindow.xaml
index 7f4423d..c17364c 100644
--- a/SourceGen/WpfGui/MainWindow.xaml
+++ b/SourceGen/WpfGui/MainWindow.xaml
@@ -80,6 +80,7 @@ limitations under the License.
                     <KeyGesture>Ctrl+L</KeyGesture>
                 </RoutedUICommand.InputGestures>
             </RoutedUICommand>
+            <RoutedUICommand x:Key="EditLocalVariableTableCmd" Text="Edit Local Variable Table..."/>
             <RoutedUICommand x:Key="EditLongCommentCmd" Text="Edit Long Comment...">
                 <RoutedUICommand.InputGestures>
                     <KeyGesture>Ctrl+M</KeyGesture>
@@ -192,6 +193,8 @@ limitations under the License.
                         CanExecute="IsProjectOpen" Executed="EditHeaderCommentCmd_Executed"/>
         <CommandBinding Command="{StaticResource EditLabelCmd}"
                         CanExecute="CanEditLabel" Executed="EditLabelCmd_Executed"/>
+        <CommandBinding Command="{StaticResource EditLocalVariableTableCmd}"
+                        CanExecute="CanEditLocalVariableTable" Executed="EditLocalVariableTableCmd_Executed"/>
         <CommandBinding Command="{StaticResource EditLongCommentCmd}"
                         CanExecute="CanEditLongComment" Executed="EditLongCommentCmd_Executed"/>
         <CommandBinding Command="{StaticResource EditNoteCmd}"
@@ -324,6 +327,7 @@ limitations under the License.
                 <MenuItem Command="{StaticResource EditLongCommentCmd}"/>
                 <MenuItem Command="{StaticResource EditNoteCmd}"/>
                 <MenuItem Command="{StaticResource EditProjectSymbolCmd}"/>
+                <MenuItem Command="{StaticResource EditLocalVariableTableCmd}"/>
                 <Separator/>
                 <MenuItem Command="{StaticResource HintAsCodeEntryPointCmd}" InputGestureText="Ctrl+H, Ctrl+C"/>
                 <MenuItem Command="{StaticResource HintAsDataStartCmd}" InputGestureText="Ctrl+H, Ctrl+D"/>
diff --git a/SourceGen/WpfGui/MainWindow.xaml.cs b/SourceGen/WpfGui/MainWindow.xaml.cs
index ab5c956..b71abbd 100644
--- a/SourceGen/WpfGui/MainWindow.xaml.cs
+++ b/SourceGen/WpfGui/MainWindow.xaml.cs
@@ -951,6 +951,10 @@ namespace SourceGen.WpfGui {
             e.CanExecute = IsProjectOpen() && mMainCtrl.CanEditLabel();
         }
 
+        private void CanEditLocalVariableTable(object sender, CanExecuteRoutedEventArgs e) {
+            e.CanExecute = IsProjectOpen() && mMainCtrl.CanEditLocalVariableTable();
+        }
+
         private void CanEditLongComment(object sender, CanExecuteRoutedEventArgs e) {
             e.CanExecute = IsProjectOpen() && mMainCtrl.CanEditLongComment();
         }
@@ -1081,6 +1085,10 @@ namespace SourceGen.WpfGui {
             mMainCtrl.EditLabel();
         }
 
+        private void EditLocalVariableTableCmd_Executed(object sender, ExecutedRoutedEventArgs e) {
+            mMainCtrl.EditLocalVariableTable();
+        }
+
         private void EditLongCommentCmd_Executed(object sender, ExecutedRoutedEventArgs e) {
             mMainCtrl.EditLongComment();
         }