diff --git a/config.c b/config.c
index 2315443..a4a6261 100644
--- a/config.c
+++ b/config.c
@@ -61,7 +61,12 @@ static enum parser_result parse_pod_setting(const char *option,
 	Integer8 i8;
 	UInteger8 u8;
 
-	if (!strcmp(option, "logAnnounceInterval")) {
+	if (!strcmp(option, "delayAsymmetry")) {
+		if (1 != sscanf(value, "%d", &val))
+			return BAD_VALUE;
+		pod->asymmetry = (Integer64) val << 16;
+
+	} else if (!strcmp(option, "logAnnounceInterval")) {
 		if (1 != sscanf(value, "%hhd", &i8))
 			return BAD_VALUE;
 		pod->logAnnounceInterval = i8;
diff --git a/default.cfg b/default.cfg
index 9cf6bbf..ee2700d 100644
--- a/default.cfg
+++ b/default.cfg
@@ -20,6 +20,7 @@ logSyncInterval		0
 logMinDelayReqInterval	0
 logMinPdelayReqInterval	0
 announceReceiptTimeout	3
+delayAsymmetry		0
 #
 # Run time options
 #
diff --git a/ds.h b/ds.h
index e96afaf..514679b 100644
--- a/ds.h
+++ b/ds.h
@@ -102,6 +102,7 @@ struct portDS {
 } PACKED;
 
 struct port_defaults {
+	Integer64 asymmetry;
 	Integer8 logAnnounceInterval;
 	Integer8 logSyncInterval;
 	Integer8 logMinDelayReqInterval;
diff --git a/gPTP.cfg b/gPTP.cfg
index 4295a40..f186e78 100644
--- a/gPTP.cfg
+++ b/gPTP.cfg
@@ -19,6 +19,7 @@ logAnnounceInterval	1
 logSyncInterval		-3
 logMinPdelayReqInterval	0
 announceReceiptTimeout	3
+delayAsymmetry		0
 #
 # Run time options
 #
diff --git a/port.c b/port.c
index 15ee8d8..8b03bd9 100644
--- a/port.c
+++ b/port.c
@@ -588,6 +588,7 @@ static int port_pdelay_request(struct port *p)
 	msg->header.ver                = PTP_VERSION;
 	msg->header.messageLength      = pdulen;
 	msg->header.domainNumber       = clock_domain_number(p->clock);
+	msg->header.correction         = -p->pod.asymmetry;
 	msg->header.sourcePortIdentity = p->portIdentity;
 	msg->header.sequenceId         = p->seqnum.delayreq++;
 	msg->header.control            = CTL_OTHER;
@@ -636,6 +637,7 @@ static int port_delay_request(struct port *p)
 	msg->header.ver                = PTP_VERSION;
 	msg->header.messageLength      = pdulen;
 	msg->header.domainNumber       = clock_domain_number(p->clock);
+	msg->header.correction         = -p->pod.asymmetry;
 	msg->header.sourcePortIdentity = p->portIdentity;
 	msg->header.sequenceId         = p->seqnum.delayreq++;
 	msg->header.control            = CTL_DELAY_REQ;
@@ -1226,11 +1228,9 @@ static void port_peer_delay(struct port *p)
 	if (rsp->header.sequenceId != ntohs(req->header.sequenceId))
 		return;
 
-	// TODO - add asymmetry value to correctionField.
-
 	t1 = timespec_to_tmv(req->hwts.ts);
 	t4 = timespec_to_tmv(rsp->hwts.ts);
-	c1 = correction_to_tmv(rsp->header.correction);
+	c1 = correction_to_tmv(rsp->header.correction + p->pod.asymmetry);
 
 	/* Process one-step response immediately. */
 	if (one_step(rsp)) {
@@ -1339,7 +1339,7 @@ static void process_sync(struct port *p, struct ptp_message *m)
 		clock_sync_interval(p->clock, p->log_sync_interval);
 	}
 
-	// TODO - add asymmetry value to correctionField.
+	m->header.correction += p->pod.asymmetry;
 
 	if (one_step(m)) {
 		port_synchronize(p, m->hwts.ts, m->ts.pdu,
diff --git a/ptp4l.8 b/ptp4l.8
index 5636a08..e12542d 100644
--- a/ptp4l.8
+++ b/ptp4l.8
@@ -134,6 +134,12 @@ option. An empty port section can be used to replace the command line option.
 
 .SH PORT OPTIONS
 
+.TP
+.B delayAsymmetry
+The time difference in nanoseconds of the transmit and receive
+paths. This value should be positive when the master-to-slave
+propagation time is longer and negative when the slave-to-master time
+is longer. The default is 0 nanoseconds.
 .TP
 .B logAnnounceInterval
 The mean time interval between Announce messages. A shorter interval makes