diff --git a/src/Makefile b/src/Makefile
index 544534f8a4ef39c6e646749269d7ad3b732cc37c..db506dae2538578a20d5d5418698465bbb3201db 100644
--- a/src/Makefile
+++ b/src/Makefile
@@ -5,6 +5,10 @@ DOCSDIR=$(SRCDIR)/../doc
 
 all: $(SUBDIRS)
 
+conly:
+	cd cluster; make conly
+	cd sphere; make conly
+
 docs:
 	cd $(DOCSDIR)/src; doxygen config.dox
 
diff --git a/src/cluster/Makefile b/src/cluster/Makefile
index 694bbc0d816dea1e2d4c4039a8967f0f973bd339..d1f3927ae0cfd2e8a245cf836d205e6971b4ae15 100644
--- a/src/cluster/Makefile
+++ b/src/cluster/Makefile
@@ -12,6 +12,8 @@ all: clu edfb np_cluster
 clu: clu.o
 	$(FC) $(FCFLAGS) -o $(BUILDDIR)/clu $(BUILDDIR)/clu.o $(LFLAGS)
 
+conly: np_cluster
+
 edfb: edfb.o
 	$(FC) $(FCFLAGS) -o $(BUILDDIR)/edfb $(BUILDDIR)/edfb.o $(LFLAGS)
 
diff --git a/src/sphere/Makefile b/src/sphere/Makefile
index f70b833d290c562539f544462ca51069c53f4a6d..3c1566bbdacdb39517936a5c969a1e5555a509d5 100644
--- a/src/sphere/Makefile
+++ b/src/sphere/Makefile
@@ -8,6 +8,8 @@ CXXLFLAGS=
 
 all: edfb sph np_sphere
 
+conly: np_sphere
+
 edfb: edfb.o
 	$(FC) $(FCFLAGS) -o $(BUILDDIR)/edfb $(BUILDDIR)/edfb.o $(LFLAGS)
 
diff --git a/src/trapping/Makefile b/src/trapping/Makefile
index bfad43bddcd843a6d71010b2a39c6e36d09e403d..592126ef874a378278a43c9d6cac6bbb5dcda700 100644
--- a/src/trapping/Makefile
+++ b/src/trapping/Makefile
@@ -14,6 +14,9 @@ lffft: lffft.o
 clean:
 	rm -f $(BUILDDIR)/*.o
 
+conly:
+	echo "Trapping not yet implemented."
+
 wipe:
 	rm -f $(BUILDDIR)/frfme $(BUILDDIR)/lffft $(BUILDDIR)/*.o