diff --git a/mps/Makefile.in b/mps/Makefile.in
index 2d558588673..e8899cce95c 100644
--- a/mps/Makefile.in
+++ b/mps/Makefile.in
@@ -1,7 +1,7 @@
 # Makefile.in -- source for autoconf Makefile
 #
 # $Id$
-# Copyright (C) 2012-2013 Ravenbrook Limited.  See end of file for license.
+# Copyright (C) 2012-2014 Ravenbrook Limited.  See end of file for license.
 #
 # YOU DON'T NEED AUTOCONF TO BUILD THE MPS
 # This is just here for people who want or expect a configure script.
@@ -17,7 +17,7 @@ MPS_TARGET_NAME=@MPS_TARGET_NAME@
 EXTRA_TARGETS=@EXTRA_TARGETS@
 prefix=$(DESTDIR)@prefix@
 TARGET_OPTS=-C code -f $(MPS_TARGET_NAME).gmk EXTRA_TARGETS="$(EXTRA_TARGETS)"
-XCODEBUILD=xcodebuild -project code/mps.xcodeproj
+XCODEBUILD=xcrun xcodebuild -project code/mps.xcodeproj
 
 all: @BUILD_TARGET@
 
diff --git a/mps/tool/testcoverage b/mps/tool/testcoverage
index ff1967031dd..dacae8cd5f4 100755
--- a/mps/tool/testcoverage
+++ b/mps/tool/testcoverage
@@ -26,14 +26,14 @@ case "$ARCH-$OS" in
         CONFIGURATION=Debug
         (
             cd -- "$CODE"
-            xcodebuild -config "$CONFIGURATION" clean
-            xcodebuild -config "$CONFIGURATION" -target testrun \
+            xcrun xcodebuild -config "$CONFIGURATION" clean
+            xcrun xcodebuild -config "$CONFIGURATION" -target testrun \
                 GCC_GENERATE_TEST_COVERAGE_FILES=YES \
                 GCC_INSTRUMENT_PROGRAM_FLOW_ARCS=YES
         )
         (
             cd -- "$CODE/xc/$PROJECT.build/$CONFIGURATION/$PROJECT.build/Objects-normal/$ARCH"
-            gcov mps.c 2> /dev/null
+            xcrun gcov mps.c 2> /dev/null
         ) | "$TOOL/gcovfmt"
         ;;
     *)