diff --git a/source/loaddata.dfm b/source/loaddata.dfm
index d0aaceaf..640f3624 100644
--- a/source/loaddata.dfm
+++ b/source/loaddata.dfm
@@ -355,7 +355,7 @@ object loaddataform: Tloaddataform
       Left = 245
       Top = 91
       Width = 23
-      Height = 44
+      Height = 66
       Align = alNone
       Anchors = [akTop, akRight]
       AutoSize = True
@@ -375,8 +375,16 @@ object loaddataform: Tloaddataform
         Top = 22
         Caption = 'btnColDown'
         ImageIndex = 75
+        Wrap = True
         OnClick = btnColMoveClick
       end
+      object btnCheckAll: TToolButton
+        Left = 0
+        Top = 44
+        Caption = 'Select / Deselect all'
+        ImageIndex = 128
+        OnClick = btnCheckAllClick
+      end
     end
   end
 end
diff --git a/source/loaddata.pas b/source/loaddata.pas
index 8e618de4..ec73bad7 100644
--- a/source/loaddata.pas
+++ b/source/loaddata.pas
@@ -52,6 +52,7 @@ type
     chkLowPriority: TCheckBox;
     chkLocalNumbers: TCheckBox;
     chkTruncateTable: TCheckBox;
+    btnCheckAll: TToolButton;
     procedure FormCreate(Sender: TObject);
     procedure FormDestroy(Sender: TObject);
     procedure editFilenameChange(Sender: TObject);
@@ -67,6 +68,7 @@ type
     procedure comboEncodingSelect(Sender: TObject);
     procedure FormClose(Sender: TObject; var Action: TCloseAction);
     procedure chklistColumnsClick(Sender: TObject);
+    procedure btnCheckAllClick(Sender: TObject);
   private
     { Private declarations }
     Encoding: TEncoding;
@@ -616,11 +618,40 @@ end;
 
 
 procedure Tloaddataform.chklistColumnsClick(Sender: TObject);
+var
+  i, CheckedNum: Integer;
 begin
   btnColDown.Enabled := (chklistColumns.ItemIndex > -1)
     and (chklistColumns.ItemIndex < chklistColumns.Count-1);
   btnColUp.Enabled := (chklistColumns.ItemIndex > -1)
     and (chklistColumns.ItemIndex > 0);
+  // Toggle icon when none is selected
+  CheckedNum := 0;
+  for i:=0 to chklistColumns.Items.Count-1 do begin
+    if chklistColumns.Checked[i] then
+      Inc(CheckedNum);
+  end;
+  if CheckedNum < chklistColumns.Items.Count then
+    btnCheckAll.ImageIndex := 128
+  else
+    btnCheckAll.ImageIndex := 127;
+end;
+
+
+procedure Tloaddataform.btnCheckAllClick(Sender: TObject);
+var
+  i, CheckedNum: Integer;
+begin
+  CheckedNum := 0;
+  for i:=0 to chklistColumns.Items.Count-1 do begin
+    if chklistColumns.Checked[i] then
+      Inc(CheckedNum);
+  end;
+  if CheckedNum < chklistColumns.Items.Count then
+    chklistColumns.CheckAll(cbChecked)
+  else
+    chklistColumns.CheckAll(cbUnchecked);
+  chklistColumns.OnClick(Sender);
 end;