diff --git a/system/core/Common.php b/system/core/Common.php
index b5a696c..504e225 100644
--- a/system/core/Common.php
+++ b/system/core/Common.php
@@ -289,7 +289,7 @@
 			$_config[0] =& get_config();
 		}
 
-		return isset($_config[0][$item]) ? $_config[0][$item] : FALSE;
+		return isset($_config[0][$item]) ? $_config[0][$item] : NULL;
 	}
 }
 
diff --git a/system/core/Exceptions.php b/system/core/Exceptions.php
index cb4bc3c..49c2217 100644
--- a/system/core/Exceptions.php
+++ b/system/core/Exceptions.php
@@ -145,9 +145,11 @@
 	 */
 	public function show_error($heading, $message, $template = 'error_general', $status_code = 500)
 	{
-		$templates_path = config_item('error_views_path')
-			? config_item('error_views_path')
-			: VIEWPATH.'errors'.DIRECTORY_SEPARATOR;
+		$templates_path = config_item('error_views_path');
+		if (empty($templates_path))
+		{
+			$templates_path = VIEWPATH.'errors'.DIRECTORY_SEPARATOR;
+		}
 
 		if (is_cli())
 		{
@@ -185,9 +187,11 @@
 	 */
 	public function show_php_error($severity, $message, $filepath, $line)
 	{
-		$templates_path = config_item('error_views_path')
-			? config_item('error_views_path')
-			: VIEWPATH.'errors'.DIRECTORY_SEPARATOR;
+		$templates_path = config_item('error_views_path');
+		if (empty($templates_path))
+		{
+			$templates_path = VIEWPATH.'errors'.DIRECTORY_SEPARATOR;
+		}
 
 		$severity = isset($this->levels[$severity]) ? $this->levels[$severity] : $severity;
 
diff --git a/system/core/Input.php b/system/core/Input.php
index ada9fc6..9ae2f6d 100644
--- a/system/core/Input.php
+++ b/system/core/Input.php
@@ -353,7 +353,7 @@
 			$path = config_item('cookie_path');
 		}
 
-		if ($secure === FALSE && config_item('cookie_secure') !== FALSE)
+		if ($secure === FALSE && config_item('cookie_secure') === TRUE)
 		{
 			$secure = config_item('cookie_secure');
 		}
diff --git a/system/core/Security.php b/system/core/Security.php
index 15a6643..cffdb9a 100755
--- a/system/core/Security.php
+++ b/system/core/Security.php
@@ -158,7 +158,7 @@
 	public function __construct()
 	{
 		// Is CSRF protection enabled?
-		if (config_item('csrf_protection') === TRUE)
+		if (config_item('csrf_protection'))
 		{
 			// CSRF config
 			foreach (array('csrf_expire', 'csrf_token_name', 'csrf_cookie_name') as $key)
@@ -170,9 +170,9 @@
 			}
 
 			// Append application specific cookie prefix
-			if (config_item('cookie_prefix'))
+			if ($cookie_prefix = config_item('cookie_prefix'))
 			{
-				$this->_csrf_cookie_name = config_item('cookie_prefix').$this->_csrf_cookie_name;
+				$this->_csrf_cookie_name = $cookie_prefix.$this->_csrf_cookie_name;
 			}
 
 			// Set the CSRF hash
diff --git a/system/libraries/Encrypt.php b/system/libraries/Encrypt.php
index 995bf0b..1af42ed 100644
--- a/system/libraries/Encrypt.php
+++ b/system/libraries/Encrypt.php
@@ -111,7 +111,7 @@
 
 			$key = config_item('encryption_key');
 
-			if ($key === FALSE)
+			if ( ! strlen($key))
 			{
 				show_error('In order to use the encryption class requires that you set an encryption key in your config file.');
 			}
diff --git a/tests/mocks/core/common.php b/tests/mocks/core/common.php
index 5c32ca5..2e8265b 100644
--- a/tests/mocks/core/common.php
+++ b/tests/mocks/core/common.php
@@ -32,7 +32,7 @@
 
 		if ( ! isset($config[$item]))
 		{
-			return FALSE;
+			return NULL;
 		}
 
 		return $config[$item];
diff --git a/user_guide_src/source/changelog.rst b/user_guide_src/source/changelog.rst
index a3b3549..0e49302 100644
--- a/user_guide_src/source/changelog.rst
+++ b/user_guide_src/source/changelog.rst
@@ -492,6 +492,7 @@
       -  Changed internal function ``load_class()`` to accept a constructor parameter instead of (previously unused) class name prefix.
       -  Removed default parameter value of :func:`is_php()`.
       -  Added a second argument ``$double_encode`` to :func:`html_escape()`.
+      -  Changed function ``config_item()`` to return NULL instead of FALSE when no value is found.
 
    -  :doc:`Output Library <libraries/output>` changes include:
 
diff --git a/user_guide_src/source/general/common_functions.rst b/user_guide_src/source/general/common_functions.rst
index 9c0a7cb..399a323 100644
--- a/user_guide_src/source/general/common_functions.rst
+++ b/user_guide_src/source/general/common_functions.rst
@@ -63,7 +63,7 @@
 .. function:: config_item($key)
 
 	:param	string	$key: Config item key
-	:returns:	Configuration key value or FALSE if not found
+	:returns:	Configuration key value or NULL if not found
 	:rtype:	mixed
 
 	The :doc:`Config Library <../libraries/config>` is the preferred way of
diff --git a/user_guide_src/source/installation/upgrade_300.rst b/user_guide_src/source/installation/upgrade_300.rst
index 6915faf..81340e6 100644
--- a/user_guide_src/source/installation/upgrade_300.rst
+++ b/user_guide_src/source/installation/upgrade_300.rst
@@ -158,6 +158,10 @@
 
 Many methods and functions now return NULL instead of FALSE when the required items don't exist:
 
+ - :doc:`Common functions <../general/common_functions>`
+
+   - config_item()
+
  - :doc:`Config Class <../libraries/config>`
 
    - config->item()