diff --git a/S7.Net.UnitTest/S7.Net.UnitTest.csproj b/S7.Net.UnitTest/S7.Net.UnitTest.csproj
index 0a14d88..a87d0e2 100644
--- a/S7.Net.UnitTest/S7.Net.UnitTest.csproj
+++ b/S7.Net.UnitTest/S7.Net.UnitTest.csproj
@@ -81,6 +81,7 @@
     <Compile Include="Properties\AssemblyInfo.cs" />
     <Compile Include="Helpers\TestLongStruct.cs" />
     <Compile Include="TypeTests\ClassTests.cs" />
+    <Compile Include="TypeTests\DtlTests.cs" />
     <Compile Include="TypeTests\DateTimeTests.cs" />
     <Compile Include="TypeTests\StringExTests.cs" />
     <Compile Include="TypeTests\StringTests.cs" />
diff --git a/S7.Net.UnitTest/TypeTests/DtlTests.cs b/S7.Net.UnitTest/TypeTests/DtlTests.cs
new file mode 100644
index 0000000..23b6217
--- /dev/null
+++ b/S7.Net.UnitTest/TypeTests/DtlTests.cs
@@ -0,0 +1,171 @@
+using System;
+using System.Linq;
+using Microsoft.VisualStudio.TestTools.UnitTesting;
+
+namespace S7.Net.UnitTest.TypeTests
+{
+    public static class DtlTests
+    {
+        private static readonly DateTime SampleDateTime = new DateTime(1993, 12, 25, 8, 12, 34, 567);
+
+        private static readonly byte[] SampleByteArray = {0x07, 0xC9, 0x0C, 0x19, 0x07, 0x08, 0x0C, 0x22, 0x21, 0xCB, 0xBB, 0xC0 };
+
+        private static readonly byte[] SpecMinByteArray =
+        {
+            0x07, 0xB2, 0x01, 0x01,  (byte) (int) (Types.Dtl.SpecMinimumDateTime.DayOfWeek + 1), 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
+        };
+
+        private static readonly byte[] SpecMaxByteArray =
+        {
+            0x08, 0xD6, 0x04, 0x0B,  (byte) (int) (Types.Dtl.SpecMaximumDateTime.DayOfWeek + 1), 0x17, 0x2F, 0x10, 0x32, 0xE7, 0x01, 0x80
+        };
+
+        [TestClass]
+        public class FromByteArray
+        {
+            [TestMethod]
+            public void Sample()
+            {
+                AssertFromByteArrayEquals(SampleDateTime, SampleByteArray);
+            }
+
+            [TestMethod]
+            public void SpecMinimum()
+            {
+                AssertFromByteArrayEquals(Types.Dtl.SpecMinimumDateTime, SpecMinByteArray);
+            }
+
+            [TestMethod]
+            public void SpecMaximum()
+            {
+                AssertFromByteArrayEquals(Types.Dtl.SpecMaximumDateTime, SpecMaxByteArray);
+            }
+
+            [TestMethod, ExpectedException(typeof(ArgumentOutOfRangeException))]
+            public void ThrowsOnLessThan12Bytes()
+            {
+                Types.Dtl.FromByteArray(new byte[11]);
+            }
+
+            [TestMethod, ExpectedException(typeof(ArgumentOutOfRangeException))]
+            public void ThrowsOnMoreTHan12Bytes()
+            {
+                Types.Dtl.FromByteArray(new byte[13]);
+            }
+
+            [TestMethod, ExpectedException(typeof(ArgumentOutOfRangeException))]
+            public void ThrowsOnInvalidYear()
+            {
+                Types.Dtl.FromByteArray(MutateSample(0, 0xa0));
+            }
+
+            [TestMethod, ExpectedException(typeof(ArgumentOutOfRangeException))]
+            public void ThrowsOnZeroMonth()
+            {
+                Types.Dtl.FromByteArray(MutateSample(2, 0x00));
+            }
+
+            [TestMethod, ExpectedException(typeof(ArgumentOutOfRangeException))]
+            public void ThrowsOnTooLargeMonth()
+            {
+                Types.Dtl.FromByteArray(MutateSample(2, 0x13));
+            }
+
+            [TestMethod, ExpectedException(typeof(ArgumentOutOfRangeException))]
+            public void ThrowsOnZeroDay()
+            {
+                Types.Dtl.FromByteArray(MutateSample(3, 0x00));
+            }
+
+            [TestMethod, ExpectedException(typeof(ArgumentOutOfRangeException))]
+            public void ThrowsOnTooLargeDay()
+            {
+                Types.Dtl.FromByteArray(MutateSample(3, 0x32));
+            }
+
+            [TestMethod, ExpectedException(typeof(ArgumentOutOfRangeException))]
+            public void ThrowsOnInvalidHour()
+            {
+                Types.Dtl.FromByteArray(MutateSample(5, 0x24));
+            }
+
+            [TestMethod, ExpectedException(typeof(ArgumentOutOfRangeException))]
+            public void ThrowsOnInvalidMinute()
+            {
+                Types.Dtl.FromByteArray(MutateSample(6, 0x60));
+            }
+
+            [TestMethod, ExpectedException(typeof(ArgumentOutOfRangeException))]
+            public void ThrowsOnInvalidSecond()
+            {
+                Types.Dtl.FromByteArray(MutateSample(7, 0x60));
+            }
+
+            [TestMethod, ExpectedException(typeof(ArgumentOutOfRangeException))]
+            public void ThrowsOnInvalidNanosecondsFirstDigit()
+            {
+                Types.Dtl.FromByteArray(MutateSample(8, 0x3B));
+            }
+
+
+            [TestMethod, ExpectedException(typeof(ArgumentOutOfRangeException))]
+            public void ThrowsOnZeroDayOfWeek()
+            {
+                Types.Dtl.FromByteArray(MutateSample(4, 0));
+            }
+
+            [TestMethod, ExpectedException(typeof(ArgumentOutOfRangeException))]
+            public void ThrowsOnTooLargeDayOfWeek()
+            {
+                Types.Dtl.FromByteArray(MutateSample(4, 8));
+            }
+
+            private static void AssertFromByteArrayEquals(DateTime expected, params byte[] bytes)
+            {
+                Assert.AreEqual(expected, Types.Dtl.FromByteArray(bytes));
+            }
+
+            private static byte[] MutateSample(int index, byte value) =>
+                SampleByteArray.Select((b, i) => i == index ? value : b).ToArray();
+        }
+
+        [TestClass]
+        public class ToByteArray
+        {
+            [TestMethod]
+            public void Sample()
+            {
+                AssertToByteArrayEquals(SampleDateTime, SampleByteArray);
+            }
+
+            [TestMethod]
+            public void SpecMinimum()
+            {
+                AssertToByteArrayEquals(Types.Dtl.SpecMinimumDateTime, SpecMinByteArray);
+            }
+
+            [TestMethod]
+            public void SpecMaximum()
+            {
+                AssertToByteArrayEquals(Types.Dtl.SpecMaximumDateTime, SpecMaxByteArray);
+            }
+
+            [TestMethod, ExpectedException(typeof(ArgumentOutOfRangeException))]
+            public void ThrowsOnTimeBeforeSpecMinimum()
+            {
+                Types.Dtl.ToByteArray(new DateTime(1950, 1, 1));
+            }
+
+            [TestMethod, ExpectedException(typeof(ArgumentOutOfRangeException))]
+            public void ThrowsOnTimeAfterSpecMaximum()
+            {
+                Types.Dtl.ToByteArray(new DateTime(2790, 1, 1));
+            }
+
+            private static void AssertToByteArrayEquals(DateTime value, params byte[] expected)
+            {
+                CollectionAssert.AreEqual(expected, Types.Dtl.ToByteArray(value));
+            }
+        }
+    }
+}
diff --git a/S7.Net/Types/Dtl.cs b/S7.Net/Types/Dtl.cs
new file mode 100644
index 0000000..1c95911
--- /dev/null
+++ b/S7.Net/Types/Dtl.cs
@@ -0,0 +1,158 @@
+using System;
+using System.Collections.Generic;
+using System.IO;
+
+namespace S7.Net.Types
+{
+    /// <summary>
+    /// Contains the methods to convert between <see cref="T:System.DateTime"/> and S7 representation of DTL values.
+    /// </summary>
+    public static class Dtl
+    {
+        /// <summary>
+        /// The minimum <see cref="T:System.DateTime"/> value supported by the specification.
+        /// </summary>
+        public static readonly System.DateTime SpecMinimumDateTime = new System.DateTime(1970, 1, 1);
+
+        /// <summary>
+        /// The maximum <see cref="T:System.DateTime"/> value supported by the specification.
+        /// </summary>
+        public static readonly System.DateTime SpecMaximumDateTime = new System.DateTime(2262, 4, 11, 23, 47, 16, 854);
+
+        /// <summary>
+        /// Parses a <see cref="T:System.DateTime"/> value from bytes.
+        /// </summary>
+        /// <param name="bytes">Input bytes read from PLC.</param>
+        /// <returns>A <see cref="T:System.DateTime"/> object representing the value read from PLC.</returns>
+        /// <exception cref="ArgumentOutOfRangeException">Thrown when the length of
+        ///   <paramref name="bytes"/> is not 12 or any value in <paramref name="bytes"/>
+        ///   is outside the valid range of values.</exception>
+        public static System.DateTime FromByteArray(byte[] bytes)
+        {
+            return FromByteArrayImpl(bytes);
+        }
+
+        /// <summary>
+        /// Parses an array of <see cref="T:System.DateTime"/> values from bytes.
+        /// </summary>
+        /// <param name="bytes">Input bytes read from PLC.</param>
+        /// <returns>An array of <see cref="T:System.DateTime"/> objects representing the values read from PLC.</returns>
+        /// <exception cref="ArgumentOutOfRangeException">Thrown when the length of
+        ///   <paramref name="bytes"/> is not a multiple of 12 or any value in
+        ///   <paramref name="bytes"/> is outside the valid range of values.</exception>
+        public static System.DateTime[] ToArray(byte[] bytes)
+        {
+            if (bytes.Length % 12 != 0)
+                throw new ArgumentOutOfRangeException(nameof(bytes), bytes.Length,
+                    $"Parsing an array of Dtl requires a multiple of 12 bytes of input data, input data is '{bytes.Length}' long.");
+
+            var cnt = bytes.Length / 12;
+            var result = new System.DateTime[cnt];
+
+            for (var i = 0; i < cnt; i++)
+            {
+                var slice = new byte[12];
+                Array.Copy(bytes, i * 12, slice, 0, 12);
+                result[i] = FromByteArrayImpl(slice);
+            }
+
+            return result;
+        }
+
+        private static System.DateTime FromByteArrayImpl(byte[] bytes)
+        {
+            if (bytes.Length != 12)
+                throw new ArgumentOutOfRangeException(nameof(bytes), bytes.Length,
+                    $"Parsing a Dtl requires exactly 12 bytes of input data, input data is {bytes.Length} bytes long.");
+
+
+            int year = AssertRangeInclusive(Word.FromBytes(bytes[1], bytes[0]), 1970, 2262, "year");
+            int month = AssertRangeInclusive(bytes[2], 1, 12, "month");
+            int day = AssertRangeInclusive(bytes[3], 1, 31, "day of month");
+            var dayOfWeek = AssertRangeInclusive(bytes[4], 1, 7, "day of week");
+            int hour = AssertRangeInclusive(bytes[5], 0, 23, "hour");
+            int minute = AssertRangeInclusive(bytes[6], 0, 59, "minute");
+            int second = AssertRangeInclusive(bytes[7], 0, 59, "second"); ;
+
+            var nanoseconds = AssertRangeInclusive<uint>(DWord.FromBytes(bytes[11], bytes[10], bytes[9], bytes[8]), 0, 999999999, "nanoseconds");
+
+            var time = new System.DateTime(year, month, day, hour, minute, second);
+            return time.AddTicks(nanoseconds / 100);
+        }
+
+        /// <summary>
+        /// Converts a <see cref="T:System.DateTime"/> value to a byte array.
+        /// </summary>
+        /// <param name="dateTime">The DateTime value to convert.</param>
+        /// <returns>A byte array containing the S7 DTL representation of <paramref name="dateTime"/>.</returns>
+        /// <exception cref="ArgumentOutOfRangeException">Thrown when the value of
+        ///   <paramref name="dateTime"/> is before <see cref="P:SpecMinimumDateTime"/>
+        ///   or after <see cref="P:SpecMaximumDateTime"/>.</exception>
+        public static byte[] ToByteArray(System.DateTime dateTime)
+        {
+            if (dateTime < SpecMinimumDateTime)
+                throw new ArgumentOutOfRangeException(nameof(dateTime), dateTime,
+                    $"Date time '{dateTime}' is before the minimum '{SpecMinimumDateTime}' supported in S7 DTL representation.");
+
+            if (dateTime > SpecMaximumDateTime)
+                throw new ArgumentOutOfRangeException(nameof(dateTime), dateTime,
+                    $"Date time '{dateTime}' is after the maximum '{SpecMaximumDateTime}' supported in S7 DTL representation.");
+
+            var stream = new MemoryStream(12);
+            // Convert Year
+            stream.Write(Word.ToByteArray(Convert.ToUInt16(dateTime.Year)), 0, 2);
+
+            // Convert Month
+            stream.WriteByte(Convert.ToByte(dateTime.Month));
+
+            // Convert Day
+            stream.WriteByte(Convert.ToByte(dateTime.Day));
+
+            // Convert WeekDay. NET DateTime starts with Sunday = 0, while S7DT has Sunday = 1.
+            stream.WriteByte(Convert.ToByte(dateTime.DayOfWeek + 1));
+
+            // Convert Hour
+            stream.WriteByte(Convert.ToByte(dateTime.Hour));
+
+            // Convert Minutes
+            stream.WriteByte(Convert.ToByte(dateTime.Minute));
+
+            // Convert Seconds
+            stream.WriteByte(Convert.ToByte(dateTime.Second));
+
+            // Convert Nanoseconds. Net DateTime has a representation of 1 Tick = 100ns.
+            // Thus First take the ticks Mod 1 Second (1s = 10'000'000 ticks), and then Convert to nanoseconds.
+            stream.Write(DWord.ToByteArray(Convert.ToUInt32(dateTime.Ticks % 10000000 * 100)), 0, 4);
+
+            return stream.ToArray();
+        }
+
+        /// <summary>
+        /// Converts an array of <see cref="T:System.DateTime"/> values to a byte array.
+        /// </summary>
+        /// <param name="dateTimes">The DateTime values to convert.</param>
+        /// <returns>A byte array containing the S7 DTL representations of <paramref name="dateTimes"/>.</returns>
+        /// <exception cref="ArgumentOutOfRangeException">Thrown when any value of
+        ///   <paramref name="dateTimes"/> is before <see cref="P:SpecMinimumDateTime"/>
+        ///   or after <see cref="P:SpecMaximumDateTime"/>.</exception>
+        public static byte[] ToByteArray(System.DateTime[] dateTimes)
+        {
+            var bytes = new List<byte>(dateTimes.Length * 8);
+            foreach (var dateTime in dateTimes) bytes.AddRange(ToByteArray(dateTime));
+
+            return bytes.ToArray();
+        }
+
+        private static T AssertRangeInclusive<T>(T input, T min, T max, string field) where T : IComparable<T>
+        {
+            if (input.CompareTo(min) < 0)
+                throw new ArgumentOutOfRangeException(nameof(input), input,
+                    $"Value '{input}' is lower than the minimum '{min}' allowed for {field}.");
+            if (input.CompareTo(max) > 0)
+                throw new ArgumentOutOfRangeException(nameof(input), input,
+                    $"Value '{input}' is higher than the maximum '{max}' allowed for {field}.");
+
+            return input;
+        }
+    }
+}
\ No newline at end of file