diff --git a/builtin-config.c b/builtin-config.c
index 077d8ef2df..2b9a4261d4 100644
--- a/builtin-config.c
+++ b/builtin-config.c
@@ -79,9 +79,10 @@ static int get_value(const char* key_, const char* regex_)
 		local = getenv(CONFIG_LOCAL_ENVIRONMENT);
 		if (!local)
 			local = repo_config = xstrdup(git_path("config"));
-		if (home)
+		if (git_config_global() && home)
 			global = xstrdup(mkpath("%s/.gitconfig", home));
-		system_wide = git_etc_gitconfig();
+		if (git_config_system())
+			system_wide = git_etc_gitconfig();
 	}
 
 	key = xstrdup(key_);
diff --git a/cache.h b/cache.h
index cdcabe92b6..efd31d8569 100644
--- a/cache.h
+++ b/cache.h
@@ -631,6 +631,9 @@ extern int git_config_set_multivar(const char *, const char *, const char *, int
 extern int git_config_rename_section(const char *, const char *);
 extern const char *git_etc_gitconfig(void);
 extern int check_repository_format_version(const char *var, const char *value);
+extern int git_env_bool(const char *, int);
+extern int git_config_system(void);
+extern int git_config_global(void);
 extern int config_error_nonbool(const char *);
 
 #define MAX_GITNAME (1000)
diff --git a/config.c b/config.c
index ad47dc34f0..7881bbc778 100644
--- a/config.c
+++ b/config.c
@@ -493,6 +493,22 @@ const char *git_etc_gitconfig(void)
 	return system_wide;
 }
 
+int git_env_bool(const char *k, int def)
+{
+	const char *v = getenv(k);
+	return v ? git_config_bool(k, v) : def;
+}
+
+int git_config_system(void)
+{
+	return !git_env_bool("GIT_CONFIG_NOSYSTEM", 0);
+}
+
+int git_config_global(void)
+{
+	return !git_env_bool("GIT_CONFIG_NOGLOBAL", 0);
+}
+
 int git_config(config_fn_t fn)
 {
 	int ret = 0;
@@ -505,7 +521,7 @@ int git_config(config_fn_t fn)
 	 * config file otherwise. */
 	filename = getenv(CONFIG_ENVIRONMENT);
 	if (!filename) {
-		if (!access(git_etc_gitconfig(), R_OK))
+		if (git_config_system() && !access(git_etc_gitconfig(), R_OK))
 			ret += git_config_from_file(fn, git_etc_gitconfig());
 		home = getenv("HOME");
 		filename = getenv(CONFIG_LOCAL_ENVIRONMENT);
@@ -513,7 +529,7 @@ int git_config(config_fn_t fn)
 			filename = repo_config = xstrdup(git_path("config"));
 	}
 
-	if (home) {
+	if (git_config_global() && home) {
 		char *user_config = xstrdup(mkpath("%s/.gitconfig", home));
 		if (!access(user_config, R_OK))
 			ret = git_config_from_file(fn, user_config);
diff --git a/t/t1500-rev-parse.sh b/t/t1500-rev-parse.sh
index e474b3f1d5..38a2bf09af 100755
--- a/t/t1500-rev-parse.sh
+++ b/t/t1500-rev-parse.sh
@@ -33,9 +33,9 @@ test_rev_parse() {
 test_rev_parse toplevel false false true ''
 
 cd .git || exit 1
-test_rev_parse .git/ true true false ''
+test_rev_parse .git/ false true false ''
 cd objects || exit 1
-test_rev_parse .git/objects/ true true false ''
+test_rev_parse .git/objects/ false true false ''
 cd ../.. || exit 1
 
 mkdir -p sub/dir || exit 1
diff --git a/t/test-lib.sh b/t/test-lib.sh
index da47bd7c9e..83889c4f46 100644
--- a/t/test-lib.sh
+++ b/t/test-lib.sh
@@ -324,8 +324,11 @@ test_done () {
 PATH=$(pwd)/..:$PATH
 GIT_EXEC_PATH=$(pwd)/..
 GIT_TEMPLATE_DIR=$(pwd)/../templates/blt
-GIT_CONFIG=.git/config
-export PATH GIT_EXEC_PATH GIT_TEMPLATE_DIR GIT_CONFIG
+unset GIT_CONFIG
+unset GIT_CONFIG_LOCAL
+GIT_CONFIG_NOSYSTEM=1
+GIT_CONFIG_NOGLOBAL=1
+export PATH GIT_EXEC_PATH GIT_TEMPLATE_DIR GIT_CONFIG_NOSYSTEM GIT_CONFIG_NOGLOBAL
 
 GITPERLLIB=$(pwd)/../perl/blib/lib:$(pwd)/../perl/blib/arch/auto/Git
 export GITPERLLIB