diff --git a/CHANGELOG b/CHANGELOG
index 6ec1e6a..311f467 100644
--- a/CHANGELOG
+++ b/CHANGELOG
@@ -114,6 +114,7 @@ xx/xx/2018 autofs-5.1.5
 - use defines for expire type.
 - remove unused function dump_master().
 - fix additional typing errors.
+- make bind mounts propagation slave by default.
 
 19/12/2017 autofs-5.1.4
 - fix spec file url.
diff --git a/include/automount.h b/include/automount.h
index bb264a1..995e280 100644
--- a/include/automount.h
+++ b/include/automount.h
@@ -551,14 +551,15 @@ struct kernel_mod_version {
 #define MOUNT_FLAG_AMD_CACHE_ALL	0x0080
 
 /* Set mount propagation for bind mounts */
-#define MOUNT_FLAG_SLAVE		0x0100
-#define MOUNT_FLAG_PRIVATE		0x0200
+#define MOUNT_FLAG_SHARED		0x0100
+#define MOUNT_FLAG_SLAVE		0x0200
+#define MOUNT_FLAG_PRIVATE		0x0400
 
 /* Use strict expire semantics if requested and kernel supports it */
-#define MOUNT_FLAG_STRICTEXPIRE		0x0400
+#define MOUNT_FLAG_STRICTEXPIRE		0x0800
 
 /* Indicator for applications to ignore the mount entry */
-#define MOUNT_FLAG_IGNORE		0x0800
+#define MOUNT_FLAG_IGNORE		0x1000
 
 struct autofs_point {
 	pthread_t thid;
diff --git a/lib/master_parse.y b/lib/master_parse.y
index f817f73..08e44b5 100644
--- a/lib/master_parse.y
+++ b/lib/master_parse.y
@@ -59,8 +59,6 @@ static long timeout;
 static long negative_timeout;
 static unsigned symlnk;
 static unsigned strictexpire;
-static unsigned slave;
-static unsigned private;
 static unsigned nobind;
 static unsigned ghost;
 extern unsigned global_selection_options;
@@ -72,6 +70,14 @@ static int tmp_argc;
 static char **local_argv;
 static int local_argc;
 
+#define PROPAGATION_SHARED	MOUNT_FLAG_SHARED
+#define PROPAGATION_SLAVE	MOUNT_FLAG_SLAVE
+#define PROPAGATION_PRIVATE	MOUNT_FLAG_PRIVATE
+#define PROPAGATION_MASK	(MOUNT_FLAG_SHARED | \
+				 MOUNT_FLAG_SLAVE  | \
+				 MOUNT_FLAG_PRIVATE)
+static unsigned int propagation;
+
 static char errstr[MAX_ERR_LEN];
 
 static unsigned int verbose;
@@ -106,7 +112,7 @@ static int master_fprintf(FILE *, char *, ...);
 %token MAP
 %token OPT_TIMEOUT OPT_NTIMEOUT OPT_NOBIND OPT_NOGHOST OPT_GHOST OPT_VERBOSE
 %token OPT_DEBUG OPT_RANDOM OPT_USE_WEIGHT OPT_SYMLINK OPT_MODE
-%token OPT_STRICTEXPIRE OPT_SLAVE OPT_PRIVATE
+%token OPT_STRICTEXPIRE OPT_SHARED OPT_SLAVE OPT_PRIVATE
 %token COLON COMMA NL DDASH
 %type <strtype> map
 %type <strtype> options
@@ -208,6 +214,7 @@ line:
 	| PATH OPT_TIMEOUT { master_notify($1); YYABORT; }
 	| PATH OPT_SYMLINK { master_notify($1); YYABORT; }
 	| PATH OPT_STRICTEXPIRE { master_notify($1); YYABORT; }
+	| PATH OPT_SHARED { master_notify($1); YYABORT; }
 	| PATH OPT_SLAVE { master_notify($1); YYABORT; }
 	| PATH OPT_PRIVATE { master_notify($1); YYABORT; }
 	| PATH OPT_NOBIND { master_notify($1); YYABORT; }
@@ -622,8 +629,9 @@ daemon_option: OPT_TIMEOUT NUMBER { timeout = $2; }
 	| OPT_NTIMEOUT NUMBER { negative_timeout = $2; }
 	| OPT_SYMLINK	{ symlnk = 1; }
 	| OPT_STRICTEXPIRE { strictexpire = 1; }
-	| OPT_SLAVE	{ slave = 1; }
-	| OPT_PRIVATE	{ private = 1; }
+	| OPT_SHARED	{ propagation = PROPAGATION_SHARED; }
+	| OPT_SLAVE	{ propagation = PROPAGATION_SLAVE; }
+	| OPT_PRIVATE	{ propagation = PROPAGATION_PRIVATE; }
 	| OPT_NOBIND	{ nobind = 1; }
 	| OPT_NOGHOST	{ ghost = 0; }
 	| OPT_GHOST	{ ghost = 1; }
@@ -697,8 +705,7 @@ static void local_init_vars(void)
 	negative_timeout = 0;
 	symlnk = 0;
 	strictexpire = 0;
-	slave = 0;
-	private = 0;
+	propagation = PROPAGATION_SLAVE;
 	nobind = 0;
 	ghost = defaults_get_browse_mode();
 	random_selection = global_selection_options & MOUNT_FLAG_RANDOM_SELECT;
@@ -888,7 +895,6 @@ int master_parse_entry(const char *buffer, unsigned int default_timeout, unsigne
 			ghost = 1;
 	}
 
-
 	if (!entry->ap) {
 		ret = master_add_autofs_point(entry, logopt, nobind, ghost, 0);
 		if (!ret) {
@@ -899,6 +905,9 @@ int master_parse_entry(const char *buffer, unsigned int default_timeout, unsigne
 			return 0;
 		}
 	}
+	entry->ap->flags &= ~(PROPAGATION_MASK);
+	entry->ap->flags |= propagation;
+
 	if (random_selection)
 		entry->ap->flags |= MOUNT_FLAG_RANDOM_SELECT;
 	if (use_weight)
@@ -907,10 +916,6 @@ int master_parse_entry(const char *buffer, unsigned int default_timeout, unsigne
 		entry->ap->flags |= MOUNT_FLAG_SYMLINK;
 	if (strictexpire)
 		entry->ap->flags |= MOUNT_FLAG_STRICTEXPIRE;
-	if (slave)
-		entry->ap->flags |= MOUNT_FLAG_SLAVE;
-	if (private)
-		entry->ap->flags |= MOUNT_FLAG_PRIVATE;
 	if (negative_timeout)
 		entry->ap->negative_timeout = negative_timeout;
 	if (mode && mode < LONG_MAX)
diff --git a/lib/master_tok.l b/lib/master_tok.l
index 7486710..87a6b95 100644
--- a/lib/master_tok.l
+++ b/lib/master_tok.l
@@ -389,6 +389,7 @@ MODE		(--mode{OPTWS}|--mode{OPTWS}={OPTWS})
 	-?symlink		{ return(OPT_SYMLINK); }
 	-?nobind		{ return(OPT_NOBIND); }
 	-?nobrowse		{ return(OPT_NOGHOST); }
+	-?shared		{ return(OPT_SHARED); }
 	-?slave			{ return(OPT_SLAVE); }
 	-?private		{ return(OPT_PRIVATE); }
 	-?strictexpire		{ return(OPT_STRICTEXPIRE); }
diff --git a/modules/mount_bind.c b/modules/mount_bind.c
index 9cba0d7..5253501 100644
--- a/modules/mount_bind.c
+++ b/modules/mount_bind.c
@@ -153,6 +153,7 @@ int mount_mount(struct autofs_point *ap, const char *root, const char *name, int
 
 	if (!symlnk && bind_works) {
 		int status, existed = 1;
+		int flags;
 
 		debug(ap->logopt, MODPREFIX "calling mkdir_path %s", fullpath);
 
@@ -190,24 +191,27 @@ int mount_mount(struct autofs_point *ap, const char *root, const char *name, int
 			      what, fstype, fullpath);
 		}
 
-		if (ap->flags & (MOUNT_FLAG_SLAVE | MOUNT_FLAG_PRIVATE)) {
-			int flags = MS_SLAVE;
-
-			if (ap->flags & MOUNT_FLAG_PRIVATE)
-				flags = MS_PRIVATE;
-
-			/* The bind mount has succeeded but if the target
-			 * mount is propagation shared propagation of child
-			 * mounts (autofs offset mounts for example) back to
-			 * the target of the bind mount must be avoided or
-			 * autofs trigger mounts will deadlock.
-			 */
-			err = mount(NULL, fullpath, NULL, flags, NULL);
-			if (err) {
-				warn(ap->logopt,
-				     "failed to set propagation for %s",
-				     fullpath, root);
-			}
+		/* The bind mount has succeeded, now set the mount propagation.
+		 *
+		 * The default is propagation shared, change it if the master
+		 * map entry has a different option specified.
+		 */
+		flags = MS_SLAVE;
+		if (ap->flags & MOUNT_FLAG_PRIVATE)
+			flags = MS_PRIVATE;
+		else if (ap->flags & MOUNT_FLAG_SHARED)
+			flags = MS_SHARED;
+
+		/* Note: If the parent mount is propagation shared propagation
+		 *  of child mounts (autofs offset mounts for example) back to
+		 *  the target of the bind mount can happen in some cases and
+		 *  must be avoided or autofs trigger mounts will deadlock.
+		 */
+		err = mount(NULL, fullpath, NULL, flags, NULL);
+		if (err) {
+			warn(ap->logopt,
+			     "failed to set propagation for %s",
+			     fullpath, root);
 		}
 
 		return 0;