diff --git a/config.php b/config.php
index ffe8adc4087..7ad1f0342cf 100644
--- a/config.php
+++ b/config.php
@@ -28,7 +28,10 @@
 $THEME->yuicssmodules = array();
 $THEME->name = 'bootstrap';
 $THEME->parents = array();
-$THEME->sheets = array('moodle', 'custom');
+
+// $THEME->sheets = array('moodle', 'custom'); // LTR-only.
+// $THEME->sheets = array('moodle-rtl', 'tinymce-rtl', 'yui2-rtl', 'forms-rtl', 'custom'); // RTL-only.
+ $THEME->sheets = array('moodle', 'moodle-ltr-rtl', 'tinymce-rtl', 'yui2-rtl', 'forms-rtl', 'custom'); // LTR & RTL.
 
 $THEME->supportscssoptimisation = false;
 
diff --git a/rtl.sh b/rtl.sh
new file mode 100755
index 00000000000..34c02d48dbd
--- /dev/null
+++ b/rtl.sh
@@ -0,0 +1,161 @@
+#!/bin/sh
+
+cp style/moodle-rtl.css rtl-wip.css
+
+# remove all indentation
+sed -i '' 's/^ *//' rtl-wip.css
+
+# add .dir-rtl to the start of every selector
+sed -i '' \
+    -e '/,$/ s/^/.dir-rtl /' \
+    -e '/ {$/ s/^/.dir-rtl /' \
+    rtl-wip.css
+
+# remove .dir-rtl from lines where it isn't appropriate e.g. @media queries 
+sed -i '' \
+    -e 's/^.dir-rtl @/@/' \
+    -e 's/^.dir-rtl .dir-rtl/.dir-rtl/' \
+    rtl-wip.css
+
+# flip the order of .dir-rtl body and clean up duplicates
+sed -i '' \
+    -e 's/^.dir-rtl body/body.dir-rtl/' \
+    -e 's/^body.dir-rtl.dir-rtl/body.dir-rtl/' \
+    rtl-wip.css
+
+# remove the space after .dir-rtl where the selector targets the body tag
+sed -i '' \
+    -e 's/^.dir-rtl .layout-option-/.dir-rtl.layout-option-/' \
+    -e 's/^.dir-rtl .path-admin/.dir-rtl.path-admin/' \
+    -e 's/^.dir-rtl .path-mod-/.dir-rtl.path-mod-/' \
+    -e 's/^.dir-rtl #page-admin-/.dir-rtl#page-admin-/' \
+    -e 's/^.dir-rtl #page-course-/.dir-rtl#page-course-/' \
+    -e 's/^.dir-rtl #page-enrol-/.dir-rtl#page-enrol-/' \
+    -e 's/^.dir-rtl #page-calendar-/.dir-rtl#page-calendar-/' \
+    -e 's/^.dir-rtl #page-tag-/.dir-rtl#page-tag-/' \
+    -e 's/^.dir-rtl #page-badges-/.dir-rtl#page-badges-/' \
+    rtl-wip.css
+
+# delete css rules that don't effect RTL
+#sed -i '' \
+    #-e '/^color: / d' \
+    #-e '/font-family: / d' \
+    #-e '/font-style: / d' \
+    #-e '/font: / d' \
+    #-e '/font-weight: / d' \
+    #-e '/white-space: / d' \
+    #-e '/word-break: / d' \
+    #-e '/word-wrap: / d' \
+    #-e '/font-size: / d' \
+    #-e '/margin-bottom: / d' \
+    #-e '/vertical-align: / d' \
+    #-e '/position: / d' \
+    #-e '/display: / d' \
+    #-e '/visibility: / d' \
+    #-e '/outline: / d' \
+    #-e '/overflow: / d' \
+    #-e '/overflow-x: / d' \
+    #-e '/overflow-y: / d' \
+    #-e '/opacity: / d' \
+    #-e '/filter: / d' \
+    #-e '/background-repeat: / d' \
+    #-e '/background-size: / d' \
+    #-e '/box-shadow: / d' \
+    #-e '/box-sizing: / d' \
+    #-e '/border-collapse: / d' \
+    #-e '/border-spacing: / d' \
+    #-e '/table-layout: / d' \
+    #-e '/z-index: / d' \
+    #-e '/height: / d' \
+    #-e '/^top: / d' \
+    #-e '/^bottom: / d' \
+    #-e '/border-top-width: / d' \
+    #-e '/border-bottom-width: / d' \
+    #-e '/text-decoration: / d' \
+    #-e '/text-transform: / d' \
+    #-e '/text-shadow: / d' \
+    #-e '/text-size-adjust: / d' \
+    #-e '/letter-spacing: / d' \
+    #-e '/page-break-inside: / d' \
+    #-e '/orphans: / d' \
+    #-e '/widows: / d' \
+    #-e '/outline-offset: / d' \
+    #-e '/user-select: / d' \
+    #-e '/pointer-events: / d' \
+    #-e '/cursor: / d' \
+    #-e '/list-style: / d' \
+    #-e '/list-style-type: / d' \
+    #-e '/content: / d' \
+    #-e '/^width: / d' \
+    #-e '/^max-width: / d' \
+    #-e '/^min-width: / d' \
+    #rtl-wip.css
+
+# each of the N; commands that follows will eat a line from the end of the file
+# there's probably a way to avoid that, but I'm tired of fighting with Mac OS X's
+# version of sed so I'll just pad the file with newlines instead.
+echo "\n\n\n\n\n\n\n\n\n\n\n\n" >> rtl-wip.css
+
+# mark rules where both left and right are set
+# sed only seems to let you do this once per sed call
+sed -i '' \
+    -e 'N;/^padding-right:.*padding-left:/ s/\n/ /;P;D' \
+    rtl-wip.css
+sed -i '' \
+    -e 'N;/^padding-left:.*padding-right:/ s/\n/ /;P;D' \
+    rtl-wip.css
+sed -i '' \
+    -e 'N;/^margin-right:.*margin-left:/ s/\n/ /;P;D' \
+    rtl-wip.css
+sed -i '' \
+    -e 'N;/^margin-left:.*margin-right:/ s/\n/ /;P;D' \
+    rtl-wip.css
+sed -i '' \
+    -e 'N;/^left:.*\nright:/s/\n/ /;P;D' \
+    rtl-wip.css
+sed -i '' \
+    -e 'N;/^right:.*\nleft:/s/\n/ /;P;D' \
+    rtl-wip.css
+sed -i '' \
+    -e 'N;/^border-left:.*\nborder-right:/s/\n/ /;P;D' \
+    rtl-wip.css
+sed -i '' \
+    -e 'N;/^border-right:.*\nborder-left:/s/\n/ /;P;D' \
+    rtl-wip.css
+
+
+# add a space to lines created above to avoid further processing
+sed -i '' \
+    -e '/^padding-right.*padding-left/ s/padding-/ padding-/' \
+    -e '/^padding-left.*padding-right/ s/padding-/ padding-/' \
+    -e '/^margin-right.*margin-left/ s/margin-/ margin-/' \
+    -e '/^margin-left.*margin-right/ s/margin-/ margin-/' \
+    -e '/^border-right.*border-left/ s/border-/ border-/' \
+    -e '/^border-left.*border-right/ s/border-/ border-/' \
+    -e '/^left:.*; right:/ s/left:/ left:/' \
+    -e '/^right:.*; left:/ s/right:/ right:/' \
+    rtl-wip.css
+
+# reset single rules from the LTR Moodle CSS
+sed -i '' \
+    -e '/^left:/a \
+    right: auto;' \
+    -e '/^margin-left:/a \
+    margin-right: auto;' \
+    -e '/^padding-left:/a \
+    padding-right: 0;' \
+    -e '/^right:/a \
+    left: auto;' \
+    -e '/^margin-right:/a \
+    margin-left: auto;' \
+    -e '/^padding-right:/a \
+    padding-left: 0;' \
+    rtl-wip.css
+
+# run the output through less, to delete empty selectors,
+# catch syntax errors and format nicely
+lessc rtl-wip.css > style/moodle-ltr-rtl.css
+
+# generate some stats on the most common usages
+awk '{ print $1 }' rtl-wip.css | sort | uniq -c | sort -r > rtl-count.txt
+