diff --git a/RetroShare.pro b/RetroShare.pro
index b6df6e491..aaa1bbfde 100644
--- a/RetroShare.pro
+++ b/RetroShare.pro
@@ -1,3 +1,5 @@
+!include("retroshare.pri"): error("Could not include file retroshare.pri")
+
 TEMPLATE = subdirs
 
 SUBDIRS += \
@@ -32,11 +34,6 @@ plugins.file = plugins/plugins.pro
 plugins.depends = retroshare_gui
 
 unix {
-	isEmpty(PREFIX)   { PREFIX = /usr }
-	isEmpty(INC_DIR)  { INC_DIR = "$${PREFIX}/include/retroshare06" }
-	isEmpty(LIB_DIR)  { LIB_DIR = "$${PREFIX}/lib" }
-	isEmpty(DATA_DIR) { DATA_DIR = "$${PREFIX}/share/RetroShare06" }
-
 	icon_files.path = "$${PREFIX}/share/icons/hicolor"
 	icon_files.files = data/24x24
 	icon_files.files += data/48x48
diff --git a/libbitdht/src/libbitdht.pro b/libbitdht/src/libbitdht.pro
index 6f705fa7d..ed576a700 100644
--- a/libbitdht/src/libbitdht.pro
+++ b/libbitdht/src/libbitdht.pro
@@ -1,3 +1,5 @@
+!include("../../retroshare.pri"): error("Could not include file ../../retroshare.pri")
+
 TEMPLATE = lib
 CONFIG += staticlib
 CONFIG -= qt
diff --git a/libresapi/src/libresapi.pro b/libresapi/src/libresapi.pro
index a7a081701..cc12e1503 100644
--- a/libresapi/src/libresapi.pro
+++ b/libresapi/src/libresapi.pro
@@ -1,3 +1,5 @@
+!include("../../retroshare.pri"): error("Could not include file ../../retroshare.pri")
+
 TEMPLATE = lib
 CONFIG += staticlib
 CONFIG -= qt
diff --git a/libretroshare/src/libretroshare.pro b/libretroshare/src/libretroshare.pro
index dca32bcd1..ba29fa605 100644
--- a/libretroshare/src/libretroshare.pro
+++ b/libretroshare/src/libretroshare.pro
@@ -1,3 +1,5 @@
+!include("../../retroshare.pri"): error("Could not include file ../../retroshare.pri")
+
 TEMPLATE = lib
 CONFIG += staticlib bitdht
 CONFIG -= qt
@@ -168,11 +170,6 @@ linux-* {
 }
 
 unix {
-	isEmpty(PREFIX)   { PREFIX = /usr }
-	isEmpty(INC_DIR)  { INC_DIR = "$${PREFIX}/include/retroshare06" }
-	isEmpty(LIB_DIR)  { LIB_DIR = "$${PREFIX}/lib" }
-	isEmpty(DATA_DIR) { DATA_DIR = "$${PREFIX}/share/RetroShare06" }
-
 	DEFINES *= LIB_DIR=\"\\\"$${LIB_DIR}\\\"\"
 	DEFINES *= DATA_DIR=\"\\\"$${DATA_DIR}\\\"\"
 
diff --git a/openpgpsdk/src/openpgpsdk.pro b/openpgpsdk/src/openpgpsdk.pro
index c0f741857..786ee5819 100644
--- a/openpgpsdk/src/openpgpsdk.pro
+++ b/openpgpsdk/src/openpgpsdk.pro
@@ -1,3 +1,5 @@
+!include("../../retroshare.pri"): error("Could not include file ../../retroshare.pri")
+
 TEMPLATE = lib
 win32 {
 	CONFIG += staticlib
diff --git a/plugins/Common/retroshare_plugin.pri b/plugins/Common/retroshare_plugin.pri
index e77626dc6..d20c1baa4 100644
--- a/plugins/Common/retroshare_plugin.pri
+++ b/plugins/Common/retroshare_plugin.pri
@@ -1,3 +1,5 @@
+!include("../../retroshare.pri"): error("Could not include file ../../retroshare.pri")
+
 TEMPLATE = lib
 CONFIG *= plugin
 
@@ -5,9 +7,6 @@ DEPENDPATH += ../../libretroshare/src/ ../../retroshare-gui/src/
 INCLUDEPATH += ../../libretroshare/src/ ../../retroshare-gui/src/
 
 unix {
-	isEmpty(PREFIX)  { PREFIX = /usr }
-	isEmpty(LIB_DIR) { LIB_DIR = "$${PREFIX}/lib" }
-
 	target.path = "$${LIB_DIR}/retroshare/extensions6"
 	INSTALLS += target
 }
diff --git a/retroshare-gui/src/retroshare-gui.pro b/retroshare-gui/src/retroshare-gui.pro
index 6e61a81e2..6632c871f 100644
--- a/retroshare-gui/src/retroshare-gui.pro
+++ b/retroshare-gui/src/retroshare-gui.pro
@@ -1,3 +1,5 @@
+!include("../../retroshare.pri"): error("Could not include file ../../retroshare.pri")
+
 QT     += network xml script
 CONFIG += qt gui uic qrc resources idle bitdht
 
@@ -110,9 +112,6 @@ linux-* {
 }
 
 unix {
-	isEmpty(PREFIX)  { PREFIX = /usr }
-	isEmpty(DATA_DIR) { DATA_DIR = "$${PREFIX}/share/RetroShare06" }
-
 	target.path = "$${PREFIX}/bin"
 	INSTALLS += target
 
diff --git a/retroshare-nogui/src/retroshare-nogui.pro b/retroshare-nogui/src/retroshare-nogui.pro
index 9d590efba..52dde1f02 100644
--- a/retroshare-nogui/src/retroshare-nogui.pro
+++ b/retroshare-nogui/src/retroshare-nogui.pro
@@ -1,3 +1,5 @@
+!include("../../retroshare.pri"): error("Could not include file ../../retroshare.pri")
+
 TEMPLATE = app
 TARGET = RetroShare06-nogui
 CONFIG += bitdht
@@ -56,8 +58,6 @@ linux-* {
 }
 
 unix {
-	isEmpty(PREFIX)  { PREFIX = /usr }
-
 	target.path = "$${PREFIX}/bin"
 	INSTALLS += target
 }
diff --git a/retroshare.pri b/retroshare.pri
new file mode 100644
index 000000000..fb20b1984
--- /dev/null
+++ b/retroshare.pri
@@ -0,0 +1,6 @@
+unix {
+	isEmpty(PREFIX)   { PREFIX   = "/usr" }
+	isEmpty(INC_DIR)  { INC_DIR  = "$${PREFIX}/include/retroshare06" }
+	isEmpty(LIB_DIR)  { LIB_DIR  = "$${PREFIX}/lib" }
+	isEmpty(DATA_DIR) { DATA_DIR = "$${PREFIX}/share/RetroShare06" }
+}