diff --git a/common.mk b/common.mk
index e579ec3772..4bcd0037d3 100644
--- a/common.mk
+++ b/common.mk
@@ -17,6 +17,7 @@ enable_shared = $(ENABLE_SHARED:no=)
 
 UNICODE_VERSION = 11.0.0
 UNICODE_EMOJI_VERSION = 11.0
+UNICODE_BETA = NO
 
 ### set the following environment variable or uncomment the line if
 ### the Unicode data files should be updated completely on every update ('make up',...).
@@ -1318,12 +1319,14 @@ CACHE_DIR = $(srcdir)/.downloaded-cache
 UNICODE_DOWNLOAD = \
 	$(BASERUBY) $(srcdir)/tool/downloader.rb \
 	    --cache-dir=$(CACHE_DIR) \
+	    --unicode-beta $(UNICODE_BETA) \
 	    -d $(UNICODE_SRC_DATA_DIR) \
 	    -p $(UNICODE_VERSION)/ucd \
 	    -e $(ALWAYS_UPDATE_UNICODE:yes=-a) unicode
 UNICODE_EMOJI_DOWNLOAD = \
 	$(BASERUBY) $(srcdir)/tool/downloader.rb \
 	    --cache-dir=$(CACHE_DIR) \
+	    --unicode-beta $(UNICODE_BETA) \
 	    -d $(UNICODE_SRC_EMOJI_DATA_DIR) \
 	    -p emoji/$(UNICODE_EMOJI_VERSION) \
 	    -e $(ALWAYS_UPDATE_UNICODE:yes=-a) unicode
diff --git a/tool/downloader.rb b/tool/downloader.rb
index ee6242676d..46f8bea96e 100644
--- a/tool/downloader.rb
+++ b/tool/downloader.rb
@@ -310,6 +310,15 @@ if $0 == __FILE__
     when '--cache-dir'
       options[:cache_dir] = ARGV[1]
       ARGV.shift
+    when '--unicode-beta'
+      options[:unicode_beta] = ARGV[1]
+      ARGV.shift
+      # TODO: Move this code further down
+      if options[:unicode_beta]=='YES'
+        raise "Not yet able to deal with Unicode Data beta versions."
+      else
+        # TODO: deal with the case that we just switched from beta to 'regular'
+      end
     when /\A--cache-dir=(.*)/m
       options[:cache_dir] = $1
     when /\A-/