diff --git a/toolbox/CMakeLists.txt b/toolbox/CMakeLists.txt
index da3e81d..7f0199c 100644
--- a/toolbox/CMakeLists.txt
+++ b/toolbox/CMakeLists.txt
@@ -29,6 +29,7 @@ set(TOOLBOX_SRC
 	realpath.c
 	dispatch.cpp
 	fpinfo.cpp
+	debug.cpp
 )
 
 
diff --git a/toolbox/debug.cpp b/toolbox/debug.cpp
new file mode 100644
index 0000000..c037673
--- /dev/null
+++ b/toolbox/debug.cpp
@@ -0,0 +1,57 @@
+/*
+ * Copyright (c) 2016, Kelvin W Sherlock
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice, this
+ *    list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
+ * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ */
+
+#include "debug.h"
+#include "toolbox.h"
+
+#include <cpu/defs.h>
+#include <cpu/CpuModule.h>
+#include <cpu/fmem.h>
+
+#include "stackframe.h"
+
+using ToolBox::Log;
+
+namespace Debug {
+
+	// pascal void DebugStr(ConstStr255Param debuggerMsg)
+	uint16_t DebugStr(uint16_t trap)
+	{
+
+		uint32_t theString;
+		uint32_t sp;
+
+		std::string s;
+
+		sp = StackFrame<4>(theString);
+
+		s = ToolBox::ReadPString(theString);
+
+		Log("%04x DebugStr(%s)\n", trap, s.c_str());
+		fprintf(stderr, "%s\n", s.c_str());
+		return 0;
+	}
+}
diff --git a/toolbox/debug.h b/toolbox/debug.h
new file mode 100644
index 0000000..78b4ba4
--- /dev/null
+++ b/toolbox/debug.h
@@ -0,0 +1,13 @@
+#ifndef __mpw_debug_h__
+#define __mpw_debug_h__
+
+#include <cstdint>
+
+namespace Debug
+{
+
+	uint16_t DebugStr(uint16_t trap);
+
+}
+
+#endif
diff --git a/toolbox/dispatch.cpp b/toolbox/dispatch.cpp
index 2a9bba0..e2a2901 100644
--- a/toolbox/dispatch.cpp
+++ b/toolbox/dispatch.cpp
@@ -48,6 +48,7 @@
 #include "stackframe.h"
 #include "toolbox.h"
 #include "utility.h"
+#include "debug.h"
 
 #include <macos/sysequ.h>
 #include <macos/errors.h>
@@ -1094,6 +1095,11 @@ namespace ToolBox {
 				d0 = OS::OSDispatch(trap);
 				break;
 
+			case 0xABFF:
+				d0 = Debug::DebugStr(trap);
+				break;
+
+
 			default:
 				fprintf(stderr, "Unsupported tool trap: %04x (%s)\n",
 						trap, TrapName(trap));
diff --git a/toolbox/toolbox.cpp b/toolbox/toolbox.cpp
index 6b4b454..b127474 100644
--- a/toolbox/toolbox.cpp
+++ b/toolbox/toolbox.cpp
@@ -51,6 +51,7 @@
 #include "sane.h"
 #include "stackframe.h"
 #include "utility.h"
+#include "debug.h"
 
 
 
@@ -665,6 +666,11 @@ namespace ToolBox {
 				d0 = OSDispatch(trap);
 				break;
 
+
+			case 0xABFF:
+				d0 = Debug::DebugStr(trap);
+				break;
+
 			default:
 				fprintf(stderr, "Unsupported tool trap: %04x (%s)\n",
 						trap, TrapName(trap));