diff --git a/Configurable/Configurable.cpp b/Configurable/Configurable.cpp
new file mode 100644
index 000000000..3478ced64
--- /dev/null
+++ b/Configurable/Configurable.cpp
@@ -0,0 +1,27 @@
+//
+//  Configurable.cpp
+//  Clock Signal
+//
+//  Created by Thomas Harte on 18/11/2017.
+//  Copyright © 2017 Thomas Harte. All rights reserved.
+//
+
+#include "Configurable.hpp"
+
+using namespace Configurable;
+
+ListSelection *BooleanSelection::list_selection() {
+	return new ListSelection(value ? "yes" : "no");
+}
+
+ListSelection *ListSelection::list_selection() {
+	return new ListSelection(value);
+}
+
+BooleanSelection *ListSelection::boolean_selection() {
+	return new BooleanSelection(value != "no" && value != "n");
+}
+
+BooleanSelection *BooleanSelection::boolean_selection() {
+	return new BooleanSelection(value);
+}
diff --git a/Configurable/Configurable.hpp b/Configurable/Configurable.hpp
index 0748331d7..7def8d64a 100644
--- a/Configurable/Configurable.hpp
+++ b/Configurable/Configurable.hpp
@@ -37,20 +37,31 @@ struct ListOption: public Option {
 	ListOption(const std::string &long_name, const std::string &short_name, const std::vector<std::string> &options) : Option(long_name, short_name), options(options) {}
 };
 
+struct BooleanSelection;
+struct ListSelection;
+
 /*!
 	Selections are responses to Options.
 */
 struct Selection {
 	virtual ~Selection() {}
+	virtual ListSelection *list_selection() = 0;
+	virtual BooleanSelection *boolean_selection() = 0;
 };
 
 struct BooleanSelection: public Selection {
 	bool value;
+
+	ListSelection *list_selection();
+	BooleanSelection *boolean_selection();
 	BooleanSelection(bool value) : value(value) {}
 };
 
 struct ListSelection: public Selection {
 	std::string value;
+	
+	ListSelection *list_selection();
+	BooleanSelection *boolean_selection();
 	ListSelection(const std::string value) : value(value) {}
 };
 
diff --git a/OSBindings/Mac/Clock Signal.xcodeproj/project.pbxproj b/OSBindings/Mac/Clock Signal.xcodeproj/project.pbxproj
index 7cca3f355..6e8532ab6 100644
--- a/OSBindings/Mac/Clock Signal.xcodeproj/project.pbxproj	
+++ b/OSBindings/Mac/Clock Signal.xcodeproj/project.pbxproj	
@@ -123,6 +123,8 @@
 		4B055AEF1FAE9BF00060FFFF /* Typer.cpp in Sources */ = {isa = PBXBuildFile; fileRef = 4B2B3A471F9B8FA70062DABF /* Typer.cpp */; };
 		4B055AF11FAE9C160060FFFF /* Accelerate.framework in Frameworks */ = {isa = PBXBuildFile; fileRef = 4BC76E6A1C98F43700E6EF73 /* Accelerate.framework */; };
 		4B055AF21FAE9C1C0060FFFF /* OpenGL.framework in Frameworks */ = {isa = PBXBuildFile; fileRef = 4B055AF01FAE9C080060FFFF /* OpenGL.framework */; };
+		4B07835A1FC11D10001D12BB /* Configurable.cpp in Sources */ = {isa = PBXBuildFile; fileRef = 4B0783591FC11D10001D12BB /* Configurable.cpp */; };
+		4B07835B1FC11D42001D12BB /* Configurable.cpp in Sources */ = {isa = PBXBuildFile; fileRef = 4B0783591FC11D10001D12BB /* Configurable.cpp */; };
 		4B08A2751EE35D56008B7065 /* Z80InterruptTests.swift in Sources */ = {isa = PBXBuildFile; fileRef = 4B08A2741EE35D56008B7065 /* Z80InterruptTests.swift */; };
 		4B08A2781EE39306008B7065 /* TestMachine.mm in Sources */ = {isa = PBXBuildFile; fileRef = 4B08A2771EE39306008B7065 /* TestMachine.mm */; };
 		4B0CCC451C62D0B3001CAC5F /* CRT.cpp in Sources */ = {isa = PBXBuildFile; fileRef = 4B0CCC421C62D0B3001CAC5F /* CRT.cpp */; };
@@ -617,6 +619,7 @@
 		4B055ABE1FAE98000060FFFF /* MachineForTarget.cpp */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.cpp.cpp; path = MachineForTarget.cpp; sourceTree = "<group>"; };
 		4B055ABF1FAE98000060FFFF /* MachineForTarget.hpp */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.cpp.h; path = MachineForTarget.hpp; sourceTree = "<group>"; };
 		4B055AF01FAE9C080060FFFF /* OpenGL.framework */ = {isa = PBXFileReference; lastKnownFileType = wrapper.framework; name = OpenGL.framework; path = System/Library/Frameworks/OpenGL.framework; sourceTree = SDKROOT; };
+		4B0783591FC11D10001D12BB /* Configurable.cpp */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.cpp.cpp; path = Configurable.cpp; sourceTree = "<group>"; };
 		4B08A2741EE35D56008B7065 /* Z80InterruptTests.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = Z80InterruptTests.swift; sourceTree = "<group>"; };
 		4B08A2761EE39306008B7065 /* TestMachine.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = TestMachine.h; sourceTree = "<group>"; };
 		4B08A2771EE39306008B7065 /* TestMachine.mm */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.objcpp; path = TestMachine.mm; sourceTree = "<group>"; };
@@ -1514,6 +1517,7 @@
 			isa = PBXGroup;
 			children = (
 				4B31B88F1FBFBCD800C140D5 /* Configurable.hpp */,
+				4B0783591FC11D10001D12BB /* Configurable.cpp */,
 			);
 			name = Configurable;
 			path = ../../Configurable;
@@ -3218,6 +3222,7 @@
 				4B055AAF1FAE85FD0060FFFF /* UnformattedTrack.cpp in Sources */,
 				4B055A7E1FAE84AA0060FFFF /* main.cpp in Sources */,
 				4B055A9F1FAE85DA0060FFFF /* HFE.cpp in Sources */,
+				4B07835B1FC11D42001D12BB /* Configurable.cpp in Sources */,
 				4B055AE71FAE9B6F0060FFFF /* Shader.cpp in Sources */,
 				4B055AEC1FAE9BA20060FFFF /* Z80Base.cpp in Sources */,
 				4B055AE31FAE9B6F0060FFFF /* TextureBuilder.cpp in Sources */,
@@ -3254,6 +3259,7 @@
 				4BCF1FA41DADC3DD0039D2E7 /* Oric.cpp in Sources */,
 				4B54C0CB1F8D92590050900F /* Keyboard.cpp in Sources */,
 				4BEA525E1DF33323007E74F2 /* Tape.cpp in Sources */,
+				4B07835A1FC11D10001D12BB /* Configurable.cpp in Sources */,
 				4B8334951F5E25B60097E338 /* C1540.cpp in Sources */,
 				4B1497921EE4B5A800CE2596 /* ZX8081.cpp in Sources */,
 				4B643F3F1D77B88000D431D6 /* DocumentController.swift in Sources */,
diff --git a/OSBindings/SDL/SConstruct b/OSBindings/SDL/SConstruct
index 479173615..35786d80a 100644
--- a/OSBindings/SDL/SConstruct
+++ b/OSBindings/SDL/SConstruct
@@ -18,6 +18,8 @@ SOURCES += glob.glob('../../Components/AY38910/*.cpp')
 
 SOURCES += glob.glob('../../Concurrency/*.cpp')
 
+SOURCES += glob.glob('../../Configurable/*.cpp')
+
 SOURCES += glob.glob('../../Inputs/*.cpp')
 
 SOURCES += glob.glob('../../Machines/*.cpp')
diff --git a/OSBindings/SDL/main.cpp b/OSBindings/SDL/main.cpp
index 02d3ec42b..bf00343e6 100644
--- a/OSBindings/SDL/main.cpp
+++ b/OSBindings/SDL/main.cpp
@@ -298,6 +298,22 @@ int main(int argc, char *argv[]) {
 	Configurable::Device *configurable_device = machine->configurable_device();
 	if(configurable_device) {
 		configurable_device->set_selections(configurable_device->get_user_friendly_selections());
+		
+		// Consider transcoding any list selections that map to Boolean options.
+		for(auto &option: configurable_device->get_options()) {
+			// Check for a corresponding selection.
+			auto selection = arguments.selections.find(option->short_name);
+			if(selection != arguments.selections.end()) {
+				// Transcode selection if necessary.
+				if(dynamic_cast<Configurable::BooleanOption *>(option.get())) {
+					arguments.selections[selection->first] =  std::unique_ptr<Configurable::Selection>(selection->second->boolean_selection());
+				}
+
+				if(dynamic_cast<Configurable::ListOption *>(option.get())) {
+					arguments.selections[selection->first] =  std::unique_ptr<Configurable::Selection>(selection->second->list_selection());
+				}
+			}
+		}
 		configurable_device->set_selections(arguments.selections);
 	}