diff --git a/Documentation/rev-list-options.txt b/Documentation/rev-list-options.txt
index 71a1fcc093..90a2c027ea 100644
--- a/Documentation/rev-list-options.txt
+++ b/Documentation/rev-list-options.txt
@@ -182,6 +182,14 @@ explicitly.
 	Pretend as if all objects mentioned by reflogs are listed on the
 	command line as `<commit>`.
 
+--alternate-refs::
+	Pretend as if all objects mentioned as ref tips of alternate
+	repositories were listed on the command line. An alternate
+	repository is any repository whose object directory is specified
+	in `objects/info/alternates`.  The set of included objects may
+	be modified by `core.alternateRefsCommand`, etc. See
+	linkgit:git-config[1].
+
 --single-worktree::
 	By default, all working trees will be examined by the
 	following options when there are more than one (see
diff --git a/connected.c b/connected.c
index 1ab481fed6..cd9b324afa 100644
--- a/connected.c
+++ b/connected.c
@@ -80,6 +80,7 @@ int check_connected(oid_iterate_fn fn, void *cb_data,
 		argv_array_push(&rev_list.args, "--all");
 	}
 	argv_array_push(&rev_list.args, "--quiet");
+	argv_array_push(&rev_list.args, "--alternate-refs");
 	if (opt->progress)
 		argv_array_pushf(&rev_list.args, "--progress=%s",
 				 _("Checking connectivity"));
diff --git a/revision.c b/revision.c
index d4aaf0ef25..0d1a30a7d7 100644
--- a/revision.c
+++ b/revision.c
@@ -1552,6 +1552,32 @@ void add_index_objects_to_pending(struct rev_info *revs, unsigned int flags)
 	free_worktrees(worktrees);
 }
 
+struct add_alternate_refs_data {
+	struct rev_info *revs;
+	unsigned int flags;
+};
+
+static void add_one_alternate_ref(const struct object_id *oid,
+				  void *vdata)
+{
+	const char *name = ".alternate";
+	struct add_alternate_refs_data *data = vdata;
+	struct object *obj;
+
+	obj = get_reference(data->revs, name, oid, data->flags);
+	add_rev_cmdline(data->revs, obj, name, REV_CMD_REV, data->flags);
+	add_pending_object(data->revs, obj, name);
+}
+
+static void add_alternate_refs_to_pending(struct rev_info *revs,
+					  unsigned int flags)
+{
+	struct add_alternate_refs_data data;
+	data.revs = revs;
+	data.flags = flags;
+	for_each_alternate_ref(add_one_alternate_ref, &data);
+}
+
 static int add_parents_only(struct rev_info *revs, const char *arg_, int flags,
 			    int exclude_parent)
 {
@@ -1954,6 +1980,7 @@ static int handle_revision_opt(struct rev_info *revs, int argc, const char **arg
 	    !strcmp(arg, "--no-walk") || !strcmp(arg, "--do-walk") ||
 	    !strcmp(arg, "--bisect") || starts_with(arg, "--glob=") ||
 	    !strcmp(arg, "--indexed-objects") ||
+	    !strcmp(arg, "--alternate-refs") ||
 	    starts_with(arg, "--exclude=") ||
 	    starts_with(arg, "--branches=") || starts_with(arg, "--tags=") ||
 	    starts_with(arg, "--remotes=") || starts_with(arg, "--no-walk="))
@@ -2440,6 +2467,8 @@ static int handle_revision_pseudo_opt(const char *submodule,
 		add_reflogs_to_pending(revs, *flags);
 	} else if (!strcmp(arg, "--indexed-objects")) {
 		add_index_objects_to_pending(revs, *flags);
+	} else if (!strcmp(arg, "--alternate-refs")) {
+		add_alternate_refs_to_pending(revs, *flags);
 	} else if (!strcmp(arg, "--not")) {
 		*flags ^= UNINTERESTING | BOTTOM;
 	} else if (!strcmp(arg, "--no-walk")) {
diff --git a/t/perf/p5600-clone-reference.sh b/t/perf/p5600-clone-reference.sh
new file mode 100755
index 0000000000..68fed66347
--- /dev/null
+++ b/t/perf/p5600-clone-reference.sh
@@ -0,0 +1,27 @@
+#!/bin/sh
+
+test_description='speed of clone --reference'
+. ./perf-lib.sh
+
+test_perf_default_repo
+
+test_expect_success 'create shareable repository' '
+	git clone --bare . shared.git
+'
+
+test_expect_success 'advance base repository' '
+	# Do not use test_commit here; its test_tick will
+	# use some ancient hard-coded date. The resulting clock
+	# skew will cause pack-objects to traverse in a very
+	# sub-optimal order, skewing the results.
+	echo content >new-file-that-does-not-exist &&
+	git add new-file-that-does-not-exist &&
+	git commit -m "new commit"
+'
+
+test_perf 'clone --reference' '
+	rm -rf dst.git &&
+	git clone --no-local --bare --reference shared.git . dst.git
+'
+
+test_done
diff --git a/t/t5618-alternate-refs.sh b/t/t5618-alternate-refs.sh
new file mode 100755
index 0000000000..3353216f09
--- /dev/null
+++ b/t/t5618-alternate-refs.sh
@@ -0,0 +1,60 @@
+#!/bin/sh
+
+test_description='test handling of --alternate-refs traversal'
+. ./test-lib.sh
+
+# Avoid test_commit because we want a specific and known set of refs:
+#
+#  base -- one
+#      \      \
+#       two -- merged
+#
+# where "one" and "two" are on separate refs, and "merged" is available only in
+# the dependent child repository.
+test_expect_success 'set up local refs' '
+	git checkout -b one &&
+	test_tick &&
+	git commit --allow-empty -m base &&
+	test_tick &&
+	git commit --allow-empty -m one &&
+	git checkout -b two HEAD^ &&
+	test_tick &&
+	git commit --allow-empty -m two
+'
+
+# We'll enter the child repository after it's set up since that's where
+# all of the subsequent tests will want to run (and it's easy to forget a
+# "-C child" and get nonsense results).
+test_expect_success 'set up shared clone' '
+	git clone -s . child &&
+	cd child &&
+	git merge origin/one
+'
+
+test_expect_success 'rev-list --alternate-refs' '
+	git rev-list --remotes=origin >expect &&
+	git rev-list --alternate-refs >actual &&
+	test_cmp expect actual
+'
+
+test_expect_success 'rev-list --not --alternate-refs' '
+	git rev-parse HEAD >expect &&
+	git rev-list HEAD --not --alternate-refs >actual &&
+	test_cmp expect actual
+'
+
+test_expect_success 'limiting with alternateRefsPrefixes' '
+	test_config core.alternateRefsPrefixes refs/heads/one &&
+	git rev-list origin/one >expect &&
+	git rev-list --alternate-refs >actual &&
+	test_cmp expect actual
+'
+
+test_expect_success 'log --source shows .alternate marker' '
+	git log --oneline --source --remotes=origin >expect.orig &&
+	sed "s/origin.* /.alternate /" <expect.orig >expect &&
+	git log --oneline --source --alternate-refs >actual &&
+	test_cmp expect actual
+'
+
+test_done