diff --git a/src/commands/CMakeLists.txt b/src/commands/CMakeLists.txt
index 3595ecce..6fc68bf2 100644
--- a/src/commands/CMakeLists.txt
+++ b/src/commands/CMakeLists.txt
@@ -5,7 +5,8 @@ include_directories (${CMAKE_SOURCE_DIR}
                      ${CMAKE_SOURCE_DIR}/src/libshared/src
                      ${TIMEW_INCLUDE_DIRS})
 
-set (commands_SRCS CmdClear.cpp
+set (commands_SRCS CmdCancel.cpp
+                   CmdClear.cpp
                    CmdConfig.cpp
                    CmdContinue.cpp
                    CmdDefault.cpp
diff --git a/src/commands/CmdCancel.cpp b/src/commands/CmdCancel.cpp
new file mode 100644
index 00000000..2f89e0bc
--- /dev/null
+++ b/src/commands/CmdCancel.cpp
@@ -0,0 +1,56 @@
+////////////////////////////////////////////////////////////////////////////////
+//
+// Copyright 2015 - 2016, Paul Beckingham, Federico Hernandez.
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included
+// in all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+// OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+// THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+// SOFTWARE.
+//
+// http://www.opensource.org/licenses/mit-license.php
+//
+////////////////////////////////////////////////////////////////////////////////
+
+#include <cmake.h>
+#include <commands.h>
+#include <timew.h>
+#include <Interval.h>
+#include <iostream>
+
+////////////////////////////////////////////////////////////////////////////////
+int CmdCancel (
+  Rules& rules,
+  Database& database)
+{
+  // If there is an open interval, cancel it.
+  auto latest = getLatestInterval (database);
+  if (  latest.range.started () &&
+      ! latest.range.ended ())
+  {
+    database.deleteInterval (latest);
+    if (rules.getBoolean ("verbose"))
+      std::cout << "Canceled active time tracking.\n";
+  }
+  else
+  {
+    if (rules.getBoolean ("verbose"))
+      std::cout << "There is no active time tracking.\n";
+  }
+
+  return 0;
+}
+
+////////////////////////////////////////////////////////////////////////////////
diff --git a/src/commands/commands.h b/src/commands/commands.h
index d2d8091e..bf6ec6e7 100644
--- a/src/commands/commands.h
+++ b/src/commands/commands.h
@@ -32,6 +32,7 @@
 #include <Database.h>
 #include <Extensions.h>
 
+int CmdCancel        (            Rules&, Database&                   );
 int CmdClear         (                                                );
 int CmdConfig        (                                                );
 int CmdContinue      (            Rules&, Database&                   );