diff --git a/cmd/zfs/zfs_main.c b/cmd/zfs/zfs_main.c
index 150bebd323a4..2c719fc47f62 100644
--- a/cmd/zfs/zfs_main.c
+++ b/cmd/zfs/zfs_main.c
@@ -4328,6 +4328,16 @@ zfs_do_send(int argc, char **argv)
 		}
 	}
 
+	if (flags.dedup) {
+		(void) fprintf(stderr,
+		    gettext("WARNING: deduplicated send is "
+		    "deprecated, and will be removed in a\n"
+		    "future release. (In the future, the flag will be "
+		    "accepted, but a\n"
+		    "regular, non-deduplicated stream will be "
+		    "generated.)\n\n"));
+	}
+
 	if (flags.parsable && flags.verbosity == 0)
 		flags.verbosity = 1;
 
diff --git a/include/libzfs_impl.h b/include/libzfs_impl.h
index 276241e936a7..45c344c83666 100644
--- a/include/libzfs_impl.h
+++ b/include/libzfs_impl.h
@@ -71,6 +71,7 @@ struct libzfs_handle {
 	int libzfs_pool_iter;
 	char libzfs_chassis_id[256];
 	boolean_t libzfs_prop_debug;
+	boolean_t libzfs_dedup_warning_printed;
 };
 
 #define	ZFSSHARE_MISS	0x01	/* Didn't find entry in cache */
diff --git a/lib/libzfs/libzfs_sendrecv.c b/lib/libzfs/libzfs_sendrecv.c
index ce6a2737b8e4..138d1ba08ec3 100644
--- a/lib/libzfs/libzfs_sendrecv.c
+++ b/lib/libzfs/libzfs_sendrecv.c
@@ -4740,6 +4740,26 @@ zfs_receive_one(libzfs_handle_t *hdl, int infd, const char *tosnap,
 			(void) printf("found clone origin %s\n", origin);
 	}
 
+	if (!hdl->libzfs_dedup_warning_printed &&
+	    (DMU_GET_FEATUREFLAGS(drrb->drr_versioninfo) &
+	    DMU_BACKUP_FEATURE_DEDUP)) {
+		(void) fprintf(stderr,
+		    gettext("WARNING: This is a deduplicated send stream.  "
+		    "The ability to send and\n"
+		    "receive deduplicated send streams is deprecated.  "
+		    "In the future, the\n"
+		    "ability to receive a deduplicated send stream with "
+		    "\"zfs receive\" will be\n"
+		    "removed. However, in the future, a utility will be "
+		    "provided to convert a\n"
+		    "deduplicated send stream to a regular "
+		    "(non-deduplicated) stream. This\n"
+		    "future utility will require that the send stream be "
+		    "located in a\n"
+		    "seek-able file, rather than provided by a pipe.\n\n"));
+		hdl->libzfs_dedup_warning_printed = B_TRUE;
+	}
+
 	boolean_t resuming = DMU_GET_FEATUREFLAGS(drrb->drr_versioninfo) &
 	    DMU_BACKUP_FEATURE_RESUMING;
 	boolean_t raw = DMU_GET_FEATUREFLAGS(drrb->drr_versioninfo) &
diff --git a/man/man8/zfs-receive.8 b/man/man8/zfs-receive.8
index 30b50914076b..a60a5c7bbb61 100644
--- a/man/man8/zfs-receive.8
+++ b/man/man8/zfs-receive.8
@@ -105,6 +105,18 @@ destroyed by using the
 .Nm zfs Cm destroy Fl d
 command.
 .Pp
+Deduplicated send streams can be generated by using the
+.Nm zfs Cm send Fl D
+command.
+\fBThe ability to send and receive deduplicated send streams is deprecated.\fR
+In the future, the ability to receive a deduplicated send stream with
+.Nm zfs Cm receive
+will be removed.
+However, in the future, a utility will be provided to convert a
+deduplicated send stream to a regular (non-deduplicated) stream.
+This future utility will require that the send stream be located in a
+seek-able file, rather than provided by a pipe.
+.Pp
 If
 .Fl o Em property Ns = Ns Ar value
 or
diff --git a/man/man8/zfs-send.8 b/man/man8/zfs-send.8
index 2561cb61cf54..1deedc214bb8 100644
--- a/man/man8/zfs-send.8
+++ b/man/man8/zfs-send.8
@@ -87,6 +87,9 @@ By default, a full stream is generated.
 .Bl -tag -width "-D"
 .It Fl D, -dedup
 Generate a deduplicated stream.
+\fBDeduplicated send is deprecated and will be removed in a future release.\fR
+(In the future, the flag will be accepted but a regular, non-deduplicated
+stream will be generated.)
 Blocks which would have been sent multiple times in the send stream will only be
 sent once.
 The receiving system must also support this feature to receive a deduplicated