diff --git a/headers/os/interface/ControlLook.h b/headers/os/interface/ControlLook.h
index 1e880ea9b4..b832a1dce8 100644
--- a/headers/os/interface/ControlLook.h
+++ b/headers/os/interface/ControlLook.h
@@ -79,7 +79,8 @@ public:
 
 	/* TODO: virtual*/
 			float				DefaultItemSpacing() const;
-	static	float				ComposeItemSpacing(float spacing);
+
+	static	float				ComposeSpacing(float spacing);
 
 			uint32				Flags(BControl* control) const;
 
diff --git a/headers/os/interface/InterfaceDefs.h b/headers/os/interface/InterfaceDefs.h
index 1e5a401096..e33e5f7621 100644
--- a/headers/os/interface/InterfaceDefs.h
+++ b/headers/os/interface/InterfaceDefs.h
@@ -223,7 +223,23 @@ enum vertical_alignment {
 	B_ALIGN_USE_FULL_HEIGHT		= -2L
 };
 
-const float B_USE_DEFAULT_SPACING = -2.0f;
+
+// Layout spacing and insets, see BControlLook::ComposeSpacing()
+
+
+enum {
+	B_USE_DEFAULT_SPACING = -2,
+	B_USE_ITEM_SPACING = -2,
+	B_USE_ITEM_INSETS = -2,
+	B_USE_HALF_ITEM_SPACING = -3,
+	B_USE_HALF_ITEM_INSETS = -3,
+	B_USE_WINDOW_INSETS = -4,
+	B_USE_WINDOW_SPACING = -4,
+	B_USE_SMALL_INSETS = -5,
+	B_USE_SMALL_SPACING = -5,
+	B_USE_BIG_INSETS = -6,
+	B_USE_BIG_SPACING = -6
+};
 
 
 // Line join and cap modes
diff --git a/src/kits/interface/ControlLook.cpp b/src/kits/interface/ControlLook.cpp
index 0c13e18c2c..9ab89514f4 100644
--- a/src/kits/interface/ControlLook.cpp
+++ b/src/kits/interface/ControlLook.cpp
@@ -51,14 +51,21 @@ BControlLook::DefaultItemSpacing() const
 
 
 float
-BControlLook::ComposeItemSpacing(float spacing)
+BControlLook::ComposeSpacing(float spacing)
 {
-	if (spacing != B_USE_DEFAULT_SPACING)
-		return spacing;
-
-	if (be_control_look)
+	// We only need to check one of each synonym (B_*_SPACING | B_*_INSETS)
+	if (spacing == B_USE_ITEM_SPACING) {
 		return be_control_look->DefaultItemSpacing();
-	return 0;
+	} else if (spacing == B_USE_HALF_ITEM_SPACING) {
+		return be_control_look->DefaultItemSpacing() * 0.5f;
+	} else if (spacing == B_USE_WINDOW_INSETS) {
+		return be_control_look->DefaultItemSpacing();
+	} else if (spacing == B_USE_SMALL_SPACING) {
+		return be_control_look->DefaultItemSpacing() * 0.7f;
+	} else if (spacing == B_USE_BIG_SPACING) {
+		return be_control_look->DefaultItemSpacing() * 1.3f;
+	}
+	return spacing;
 }
 
 
diff --git a/src/kits/interface/GridLayout.cpp b/src/kits/interface/GridLayout.cpp
index 740cc2f7c3..ad0791e9a7 100644
--- a/src/kits/interface/GridLayout.cpp
+++ b/src/kits/interface/GridLayout.cpp
@@ -253,7 +253,7 @@ BGridLayout::VerticalSpacing() const
 void
 BGridLayout::SetHorizontalSpacing(float spacing)
 {
-	spacing = BControlLook::ComposeItemSpacing(spacing);
+	spacing = BControlLook::ComposeSpacing(spacing);
 	if (spacing != fHSpacing) {
 		fHSpacing = spacing;
 
@@ -265,7 +265,7 @@ BGridLayout::SetHorizontalSpacing(float spacing)
 void
 BGridLayout::SetVerticalSpacing(float spacing)
 {
-	spacing = BControlLook::ComposeItemSpacing(spacing);
+	spacing = BControlLook::ComposeSpacing(spacing);
 	if (spacing != fVSpacing) {
 		fVSpacing = spacing;
 
@@ -277,8 +277,8 @@ BGridLayout::SetVerticalSpacing(float spacing)
 void
 BGridLayout::SetSpacing(float horizontal, float vertical)
 {
-	horizontal = BControlLook::ComposeItemSpacing(horizontal);
-	vertical = BControlLook::ComposeItemSpacing(vertical);
+	horizontal = BControlLook::ComposeSpacing(horizontal);
+	vertical = BControlLook::ComposeSpacing(vertical);
 	if (horizontal != fHSpacing || vertical != fVSpacing) {
 		fHSpacing = horizontal;
 		fVSpacing = vertical;
diff --git a/src/kits/interface/GroupLayout.cpp b/src/kits/interface/GroupLayout.cpp
index 13b7fc10f1..37cdb1ac29 100644
--- a/src/kits/interface/GroupLayout.cpp
+++ b/src/kits/interface/GroupLayout.cpp
@@ -68,7 +68,7 @@ BGroupLayout::Spacing() const
 void
 BGroupLayout::SetSpacing(float spacing)
 {
-	spacing = BControlLook::ComposeItemSpacing(spacing);
+	spacing = BControlLook::ComposeSpacing(spacing);
 	if (spacing != fHSpacing) {
 		fHSpacing = spacing;
 		fVSpacing = spacing;
diff --git a/src/kits/interface/SplitLayout.cpp b/src/kits/interface/SplitLayout.cpp
index ba4ae1b658..71d7350ada 100644
--- a/src/kits/interface/SplitLayout.cpp
+++ b/src/kits/interface/SplitLayout.cpp
@@ -162,7 +162,7 @@ BSplitLayout::BSplitLayout(enum orientation orientation,
 	fTopInset(0),
 	fBottomInset(0),
 	fSplitterSize(6),
-	fSpacing(BControlLook::ComposeItemSpacing(spacing)),
+	fSpacing(BControlLook::ComposeSpacing(spacing)),
 
 	fSplitterItems(),
 	fVisibleItems(),
@@ -268,10 +268,10 @@ BSplitLayout::~BSplitLayout()
 void
 BSplitLayout::SetInsets(float left, float top, float right, float bottom)
 {
-	fLeftInset = BControlLook::ComposeItemSpacing(left);
-	fTopInset = BControlLook::ComposeItemSpacing(top);
-	fRightInset = BControlLook::ComposeItemSpacing(right);
-	fBottomInset = BControlLook::ComposeItemSpacing(bottom);
+	fLeftInset = BControlLook::ComposeSpacing(left);
+	fTopInset = BControlLook::ComposeSpacing(top);
+	fRightInset = BControlLook::ComposeSpacing(right);
+	fBottomInset = BControlLook::ComposeSpacing(bottom);
 
 	InvalidateLayout();
 }
@@ -302,7 +302,7 @@ BSplitLayout::Spacing() const
 void
 BSplitLayout::SetSpacing(float spacing)
 {
-	spacing = BControlLook::ComposeItemSpacing(spacing);
+	spacing = BControlLook::ComposeSpacing(spacing);
 	if (spacing != fSpacing) {
 		fSpacing = spacing;
 
diff --git a/src/kits/interface/TwoDimensionalLayout.cpp b/src/kits/interface/TwoDimensionalLayout.cpp
index e6219610c7..f2e0731f26 100644
--- a/src/kits/interface/TwoDimensionalLayout.cpp
+++ b/src/kits/interface/TwoDimensionalLayout.cpp
@@ -285,10 +285,10 @@ void
 BTwoDimensionalLayout::SetInsets(float left, float top, float right,
 	float bottom)
 {
-	fLeftInset = BControlLook::ComposeItemSpacing(left);
-	fTopInset = BControlLook::ComposeItemSpacing(top);
-	fRightInset = BControlLook::ComposeItemSpacing(right);
-	fBottomInset = BControlLook::ComposeItemSpacing(bottom);
+	fLeftInset = BControlLook::ComposeSpacing(left);
+	fTopInset = BControlLook::ComposeSpacing(top);
+	fRightInset = BControlLook::ComposeSpacing(right);
+	fBottomInset = BControlLook::ComposeSpacing(bottom);
 
 	InvalidateLayout();
 }