diff --git a/Mmakefile b/Mmakefile
index 1595be8c2..5fe2537ff 100644
--- a/Mmakefile
+++ b/Mmakefile
@@ -425,8 +425,8 @@ install_grades: scripts
 	# runs the newly installed compiler, rather than using the
 	# bootstrap compiler.
 	#
-	+for grade in x $(LIBGRADES); do \
-	    if [ "$$grade" != "x" ]; then \
+	+for grade in $(LIBGRADES); do \
+	    if [ "$$grade" != "$(GRADE)" ]; then \
 	    	gc_grade=`scripts/ml --grade $$grade --print-gc-grade`; \
 	        ( cd boehm_gc && \
 		  $(SUBDIR_MMAKE) MC=mmc GRADE=$$grade GC_GRADE=$$gc_grade \
@@ -485,7 +485,7 @@ install_split_library: scripts dep_library
 	done || true && \
 	{ mv -f $(deps_subdir)*.dep $(deps_subdir)*.dv *.$O Mercury/os/*.$O \
 		*.$A *.so tmp_dir || true; } && \
-	for grade in $(GRADE) $(LIBGRADES); do \
+	for grade in $(LIBGRADES); do \
 	        $(SUBDIR_MMAKE) MC=mmc GRADE=$$grade depend && \
 	        $(SUBDIR_MMAKE) MC=mmc GRADE=$$grade install_split_library || \
 			{ scripts/mercury_cleanup_install; exit 1; }; \
diff --git a/compiler/make.program_target.m b/compiler/make.program_target.m
index 6f7f825c7..6ace24b5a 100644
--- a/compiler/make.program_target.m
+++ b/compiler/make.program_target.m
@@ -493,8 +493,9 @@ install_library(MainModuleName, Succeeded, Info0, Info) -->
 		{ GradeSucceeded = yes }
 	->
 		% XXX With Mmake, LIBGRADES is target-specific.
-        	globals__io_lookup_accumulating_option(libgrades, LibGrades),
+        	globals__io_lookup_accumulating_option(libgrades, LibGrades0),
 		globals__io_lookup_bool_option(keep_going, KeepGoing),
+		{ LibGrades = list__delete_all(LibGrades0, Grade) },
         	foldl2_maybe_stop_at_error(KeepGoing,
 			install_library_grade(LinkSucceeded,
 				MainModuleName, AllModules),
diff --git a/configure.in b/configure.in
index 6736b007a..64a1d8e36 100644
--- a/configure.in
+++ b/configure.in
@@ -2299,17 +2299,6 @@ fi
 
 MERCURY_MSG("using \`$LIBGRADES' as the set of library grades to install")
 
-# Remove GRADE from LIBGRADES.  This is done because `mmake install_main'
-# will have already installed the libraries for grade GRADE.
-# We can only do this if GRADE is the same as DEFAULT_GRADE,
-# because LIBGRADES is used both for installing the compiler, which
-# gets build in grade GRADE, and also for installing user libraries,
-# which (presumably) get built in in DEFAULT_GRADE.
-if test $GRADE = $DEFAULT_GRADE; then
-	LIBGRADES=` echo " $LIBGRADES " | sed "s/ $GRADE / /" `
-fi
-
-
 LIBGRADE_OPTS=
 for libgrade in $LIBGRADES
 do
diff --git a/scripts/Mmake.rules b/scripts/Mmake.rules
index 92918c3ec..3dfbfa06a 100644
--- a/scripts/Mmake.rules
+++ b/scripts/Mmake.rules
@@ -494,8 +494,8 @@ lib%.install_grades:
 	done && \
 	{ mv -f $(deps_subdir)$*.dep $(deps_subdir)$*.dv \
 		*.a *.so tmp_dir || true; } && \
-	for grade in x $(ALL_LIBGRADES); do \
-		if [ "$$grade" != "x" ]; then \
+	for grade in $(ALL_LIBGRADES); do \
+		if [ "$$grade" != "$(GRADE)" ]; then \
 			$(MMAKE) GRADE=$$grade $*.depend || \
 				exit 1; \
 			$(MMAKE) GRADE=$$grade lib$*.install_library || \
@@ -523,8 +523,8 @@ lib%.install_split_grades:
 	mkdir tmp_dir && \
 	{ mv -f $(deps_subdir)$*.dep $(deps_subdir)$*.dv $($*.mihs) \
 		$($*.dirs) *.a *.so tmp_dir || true; } && \
-	for grade in x $(ALL_LIBGRADES); do \
-		if [ "$$grade" != "x" ]; then \
+	for grade in $(ALL_LIBGRADES); do \
+		if [ "$$grade" != "$(GRADE)" ]; then \
 			$(MMAKE) GRADE=$$grade $*.depend || \
 				exit 1; \
 			$(MMAKE) GRADE=$$grade lib$*.install_split_library || \
diff --git a/scripts/Mmake.vars.in b/scripts/Mmake.vars.in
index 72b2c9471..9c6d84439 100644
--- a/scripts/Mmake.vars.in
+++ b/scripts/Mmake.vars.in
@@ -343,7 +343,6 @@ EXTRA_RANLIBFLAGS =
 
 # List of grades to install for a library
 ALL_LIBGRADES	= $(TARGET_LIBGRADES) $(EXTRA_TARGET_LIBGRADES)
-LIBGRADES	=
 EXTRA_LIBGRADES	=
 
 # $(CFLAGS_FOR_PIC) is passed to the C compiler when creating `.pic_o' files
@@ -706,7 +705,8 @@ FINAL_INSTALL_MERC_LIB_DIR = \
 
 #-----------------------------------------------------------------------------#
 
-# Specify the additional compilation models to install by default
+# Specify the compilation models to install by default.
+# This list will include the default grade.
 LIBGRADES		= @LIBGRADES@
 
 #-----------------------------------------------------------------------------#