diff --git a/index.js b/index.js
index 95be682..8e9eedf 100644
--- a/index.js
+++ b/index.js
@@ -1,4 +1,4 @@
-
+'use strict';
 // Copyright 2015-2016 Stephen Vickers <stephen.vickers.sv@gmail.com>
 
 var dgram = require("dgram");
@@ -81,7 +81,29 @@ function Client(target, options) {
 	if (this.transport === Transport.Tls) {
 		this.tlsCA = options.tlsCA;
 	}
-
+	/* options.structuredData = {
+	 *   id1: { param1: value1, param2: value2 },
+	 *   id2: { param1: value1, param2: value2 },
+	 * }
+	 */
+	if (!options.structuredData)
+		this.sdString = '-';
+        else {
+		const elements = options.structuredData;
+		const elArr = [];
+		this.rfc3164 = false;
+		for (let sdId in elements) {
+			const paramArr = [];
+			for (let sdParamName in elements[sdId]) {
+				paramArr.push(`${sdParamName}="${elements[sdId][sdParamName]}"`);
+			}
+			elArr.push(`[${sdId} ${paramArr.join(' ')}]`);
+		}
+		if (!elArr.length)
+			this.sdString = '-';
+		else
+			this.sdString = elArr.join(' ');
+	}
 	return this;
 }
 
@@ -144,7 +166,7 @@ Client.prototype.buildFormattedMessage = function buildFormattedMessage(message,
 				+ process.pid
 				+ " "
 				+ msgid
-				+ " - "				// no STRUCTURED-DATA
+				+ ` ${this.sdString} `		// STRUCTURED-DATA
 				+ message
 				+ newline;
 	}