diff --git a/SacsCoreUnitTests/Standard/Base/Utils/StringUtil_Tester.cs b/SacsCoreUnitTests/Standard/Base/Utils/StringUtil_Tester.cs
index dcdd71e..9e1c803 100644
--- a/SacsCoreUnitTests/Standard/Base/Utils/StringUtil_Tester.cs
+++ b/SacsCoreUnitTests/Standard/Base/Utils/StringUtil_Tester.cs
@@ -12,10 +12,42 @@ namespace Sarand.UnitTests.Core.Base.Utils
 		private Random random = new Random();
 
 		//-------------------------------------------------------------------
-		//                           P a d d i n g
+		// Properties.
 		//-------------------------------------------------------------------
 		[TestMethod]
-		public void StringUtil_PadLeft ()
+		public void StringUtil_IsEmpty()
+		{
+			// Leading spaces.
+			Assert.AreEqual(true, StringUtil.IsEmpty(null));
+			Assert.AreEqual(true, StringUtil.IsEmpty(""));
+			Assert.AreEqual(false, StringUtil.IsEmpty(" "));
+			Assert.AreEqual(false, StringUtil.IsEmpty("A"));
+			Assert.AreEqual(false, StringUtil.IsEmpty("Abc"));
+			Assert.AreEqual(true, "".IsEmpty());
+			Assert.AreEqual(false, "Abc".IsEmpty());
+		}
+
+		[TestMethod]
+		public void StringUtil_IsBlank()
+		{
+			// Leading spaces.
+			Assert.AreEqual(true, StringUtil.IsBlank(null));
+			Assert.AreEqual(true, StringUtil.IsBlank(""));
+			Assert.AreEqual(true, StringUtil.IsBlank(" "));
+			Assert.AreEqual(true, StringUtil.IsBlank("    "));
+			Assert.AreEqual(true, StringUtil.IsBlank(" \n\t "));
+			Assert.AreEqual(false, StringUtil.IsBlank("A"));
+			Assert.AreEqual(false, StringUtil.IsBlank("Abc"));
+			Assert.AreEqual(true, "".IsBlank());
+			Assert.AreEqual(true, " ".IsBlank());
+			Assert.AreEqual(false, "Abc".IsBlank());
+		}
+
+		//-------------------------------------------------------------------
+		// Padding.
+		//-------------------------------------------------------------------
+		[TestMethod]
+		public void StringUtil_PadLeft()
 		{
 			// Leading spaces.
 			Assert.AreEqual("   ", "".PadLeft(3, ' '));
diff --git a/SacsStandardBase/Base/Utils/StringUtil.cs b/SacsStandardBase/Base/Utils/StringUtil.cs
index 7b5e236..3d0be83 100644
--- a/SacsStandardBase/Base/Utils/StringUtil.cs
+++ b/SacsStandardBase/Base/Utils/StringUtil.cs
@@ -12,30 +12,34 @@ namespace Sarand.Net.Standard.Base.Utils
 	public static class StringUtil
 	{
 		//-------------------------------------------------------------------
-		//                         U t i l i t i e s
+		// Definitions.
+		public static Regex RegEx_Whitespace = new Regex("\\s+");
+		public static Regex RegEx_Whitespace_Match = new Regex("^\\s+$");
+
+		//-------------------------------------------------------------------
+		// Properties.
 		//-------------------------------------------------------------------
-		public static String EmptyOnNull (String value)
-		{
-			return (value == null ? String.Empty : value);
-		}
-		public static String OnEmpty (String value, String defaultValue)
-		{
-			if (IsEmpty(value)) return defaultValue;
-			return value;
-		}
 		public static int GetLength (String value)
 		{
 			if (String.IsNullOrEmpty(value)) return 0;
 			return value.Length;
 		}
 
-		//-------------------------------------------------------------------
-		//                        C o m p a r i s o n
-		//-------------------------------------------------------------------
-		public static bool IsEmpty (this string value)
+		/// <summary>Test for null or empty value.</summary>
+		public static bool IsEmpty(this string value)
 		{
 			return String.IsNullOrEmpty(value);
 		}
+
+		/// <summary>Test for null, empty or a value that consists of whitespace characters only.</summary>
+		public static bool IsBlank(this string value)
+		{
+			return String.IsNullOrEmpty(value) || Match(value, RegEx_Whitespace_Match);
+		}
+
+		//-------------------------------------------------------------------
+		// Comparison.
+		//-------------------------------------------------------------------
 		public static bool EqualsCI (this String value1, String value2)
 		{
 			return String.Equals(value1, value2, StringComparison.OrdinalIgnoreCase);
@@ -56,6 +60,64 @@ namespace Sarand.Net.Standard.Base.Utils
 			return (value1.IndexOf(value2, StringComparison.OrdinalIgnoreCase) >= 0);
 		}
 
+		//-------------------------------------------------------------------
+		// Regular expressions.
+		//-------------------------------------------------------------------
+		/// <summary>
+		/// Create Regex from (quoted) expression and apply Regex.Match to String value and return Match.Success.
+		/// <para>- Case sensitive.</para>
+		/// </summary>
+		public static bool Match(this String value, String expression)
+		{
+			return value.Match(expression, RegexOptions.None);
+		}
+		/// <summary>
+		/// Create Regex from (quoted) expression and apply Regex.Match to String value and return Match.Success.
+		/// <para>- Case insensitive.</para>
+		/// </summary>
+		public static bool MatchCI(this String value, String expression)
+		{
+			return value.Match(expression, RegexOptions.IgnoreCase);
+		}
+		/// <summary>
+		/// Create Regex from (quoted) expression and apply Regex.Match to String value and return Match.Success.
+		/// <para>- Supply options as required.</para>
+		/// </summary>
+		public static bool Match(this String value, String expression, RegexOptions options)
+		{
+			return new Regex(Regex.Escape(expression), options).Match(value).Success;
+		}
+		/// <summary>
+		/// Apply Regex.Match to String value and return Match.Success.
+		/// </summary>
+		public static bool Match(this String value, Regex re)
+		{
+			return re.Match(value).Success;
+		}
+		/// <summary>
+		/// Apply Regex.Matches to String value and return true if any matches found.
+		/// </summary>
+		public static bool Matches(this String value, Regex re)
+		{
+			return re.Matches(value).Count < 1;
+		}
+
+		//-------------------------------------------------------------------
+		// Alternative Content.
+		//-------------------------------------------------------------------
+		public static String EmptyOnNull(String value)
+		{
+			return (value == null ? String.Empty : value);
+		}
+		public static String OnEmpty(String value, String defaultValue)
+		{
+			return (!IsEmpty(value)) ? value : defaultValue;
+		}
+		public static String OnBlank(String value, String defaultValue)
+		{
+			return (!IsBlank(value)) ? value : defaultValue;
+		}
+
 		//-------------------------------------------------------------------
 		//                           C o n t e n t
 		//-------------------------------------------------------------------