diff --git a/airtime_mvc/application/configs/constants.php b/airtime_mvc/application/configs/constants.php
index 7b27bc891..45bdbd123 100644
--- a/airtime_mvc/application/configs/constants.php
+++ b/airtime_mvc/application/configs/constants.php
@@ -19,6 +19,7 @@ define('LICENSE_URL'        , 'http://www.gnu.org/licenses/agpl-3.0-standalone.h
 define('AIRTIME_COPYRIGHT_DATE' , '2010-2012');
 define('AIRTIME_REST_VERSION'   , '1.1');
 define('AIRTIME_API_VERSION'    , '1.1');
+define('AIRTIME_CODE_VERSION'   , '2.5.2');
 
 // Metadata Keys for files
 define('MDATA_KEY_FILEPATH'    , 'filepath');
diff --git a/airtime_mvc/application/controllers/UpgradeController.php b/airtime_mvc/application/controllers/UpgradeController.php
new file mode 100644
index 000000000..2691f270f
--- /dev/null
+++ b/airtime_mvc/application/controllers/UpgradeController.php
@@ -0,0 +1,78 @@
+<?php
+
+require_once("Upgrades.php");
+
+class UpgradeController extends Zend_Controller_Action
+{
+    public function indexAction()
+    {
+        $this->view->layout()->disableLayout();
+        $this->_helper->viewRenderer->setNoRender(true);
+        
+        if (!$this->verifyAuth()) {
+            return;
+        }
+
+        $upgraders = array();
+        array_push($upgraders, new AirtimeUpgrader252());
+        /* These upgrades do not apply to open source Airtime yet.
+        array_push($upgraders, new AirtimeUpgrader253());
+        array_push($upgraders, new AirtimeUpgrader254());
+        */
+        $didWePerformAnUpgrade = false;
+        try 
+        {
+            for ($i = 0; $i < count($upgraders); $i++)
+            {
+                $upgrader = $upgraders[$i];
+                if ($upgrader->checkIfUpgradeSupported())
+                {
+                	// pass __DIR__ to the upgrades, since __DIR__ returns parent dir of file, not executor
+                    $upgrader->upgrade(__DIR__); //This will throw an exception if the upgrade fails.
+                    $didWePerformAnUpgrade = true;
+                    $this->getResponse()
+                         ->setHttpResponseCode(200)
+                         ->appendBody("Upgrade to Airtime " . $upgrader->getNewVersion() . " OK<br>"); 
+                    $i = 0; //Start over, in case the upgrade handlers are not in ascending order.
+                }
+            }
+            
+            if (!$didWePerformAnUpgrade)
+            {
+                $this->getResponse()
+                	 ->setHttpResponseCode(200)
+                	 ->appendBody("No upgrade was performed. The current Airtime version is " . AirtimeUpgrader::getCurrentVersion() . ".<br>");
+            }
+        } 
+        catch (Exception $e) 
+        {
+            $this->getResponse()
+            	 ->setHttpResponseCode(400)
+           		 ->appendBody($e->getMessage());
+        }
+    }
+
+    private function verifyAuth()
+    {
+        //The API key is passed in via HTTP "basic authentication":
+        //http://en.wikipedia.org/wiki/Basic_access_authentication
+        
+        $CC_CONFIG = Config::getConfig();
+        
+        //Decode the API key that was passed to us in the HTTP request.
+        $authHeader = $this->getRequest()->getHeader("Authorization");
+
+        $encodedRequestApiKey = substr($authHeader, strlen("Basic "));
+        $encodedStoredApiKey = base64_encode($CC_CONFIG["apiKey"][0] . ":");
+
+        if ($encodedRequestApiKey !== $encodedStoredApiKey)
+        {
+            $this->getResponse()
+                 ->setHttpResponseCode(401)
+                 ->appendBody("Error: Incorrect API key.<br>");
+            return false;
+        }
+        return true;
+    }
+
+}
diff --git a/airtime_mvc/application/controllers/upgrade_sql/airtime_2.5.3/upgrade.sql b/airtime_mvc/application/controllers/upgrade_sql/airtime_2.5.3/upgrade.sql
new file mode 100644
index 000000000..6c7980983
--- /dev/null
+++ b/airtime_mvc/application/controllers/upgrade_sql/airtime_2.5.3/upgrade.sql
@@ -0,0 +1,6 @@
+DELETE FROM cc_pref WHERE keystr = 'system_version';
+INSERT INTO cc_pref (keystr, valstr) VALUES ('system_version', '2.5.3');
+
+ALTER TABLE cc_files DROP COLUMN state;
+ALTER TABLE cc_files ADD import_status integer default 1; -- Default is "pending"
+UPDATE cc_files SET import_status=0; -- Existing files are already "imported"
diff --git a/airtime_mvc/application/controllers/upgrade_sql/airtime_2.5.5/upgrade.sql b/airtime_mvc/application/controllers/upgrade_sql/airtime_2.5.5/upgrade.sql
new file mode 100644
index 000000000..191eb2084
--- /dev/null
+++ b/airtime_mvc/application/controllers/upgrade_sql/airtime_2.5.5/upgrade.sql
@@ -0,0 +1,5 @@
+DELETE FROM cc_pref WHERE keystr = 'system_version';
+INSERT INTO cc_pref (keystr, valstr) VALUES ('system_version', '2.5.5');
+
+ALTER TABLE cc_show ADD COLUMN image_path varchar(255) DEFAULT '';
+ALTER TABLE cc_show_instances ADD COLUMN description varchar(255) DEFAULT '';
diff --git a/airtime_mvc/application/upgrade/Upgrades.php b/airtime_mvc/application/upgrade/Upgrades.php
new file mode 100644
index 000000000..f95216bd0
--- /dev/null
+++ b/airtime_mvc/application/upgrade/Upgrades.php
@@ -0,0 +1,292 @@
+<?php
+
+abstract class AirtimeUpgrader
+{
+    /** Versions that this upgrader class can upgrade from (an array of version strings). */
+    abstract protected function getSupportedVersions();
+    /** The version that this upgrader class will upgrade to. (returns a version string) */
+    abstract public function getNewVersion();
+
+    public static function getCurrentVersion()
+    {
+        CcPrefPeer::clearInstancePool(); //Ensure we don't get a cached Propel object (cached DB results) 
+                                         //because we're updating this version number within this HTTP request as well.
+        $pref = CcPrefQuery::create()
+        ->filterByKeystr('system_version')
+        ->findOne();
+        $airtime_version = $pref->getValStr();
+        return $airtime_version;
+    }
+    
+    /** 
+     * This function checks to see if this class can perform an upgrade of your version of Airtime
+     * @return boolean True if we can upgrade your version of Airtime.
+     */
+    public function checkIfUpgradeSupported()
+    {        
+        if (!in_array(AirtimeUpgrader::getCurrentVersion(), $this->getSupportedVersions())) {
+            return false;
+        }
+        return true;
+    }
+    
+    protected function toggleMaintenanceScreen($toggle)
+    {
+        if ($toggle)
+        {
+            //Disable Airtime UI
+            //create a temporary maintenance notification file
+            //when this file is on the server, zend framework redirects all
+            //requests to the maintenance page and sets a 503 response code
+            $this->maintenanceFile = isset($_SERVER['AIRTIME_BASE']) ? $_SERVER['AIRTIME_BASE']."maintenance.txt" : "/tmp/maintenance.txt";
+            $file = fopen($this->maintenanceFile, 'w');
+            fclose($file);
+        } else {
+            //delete maintenance.txt to give users access back to Airtime
+            if ($this->maintenanceFile) {
+                unlink($this->maintenanceFile);
+            }
+        }
+    }
+            
+    /** Implement this for each new version of Airtime */
+    abstract public function upgrade();
+}
+
+/** This upgrade adds schema changes to accommodate show artwork and show instance descriptions */
+class AirtimeUpgrader252 extends AirtimeUpgrader {
+	protected function getSupportedVersions() {
+		return array (
+            '2.5.1'
+		);
+	}
+	
+	public function getNewVersion() {
+		return '2.5.2';
+	}
+	
+	public function upgrade($dir = __DIR__) {
+		Cache::clear();
+		assert($this->checkIfUpgradeSupported());
+		
+		$newVersion = $this->getNewVersion();
+		
+		try {
+			$this->toggleMaintenanceScreen(true);
+			Cache::clear();
+			
+			// Begin upgrade
+			$airtimeConf = isset($_SERVER['AIRTIME_CONF']) ? $_SERVER['AIRTIME_CONF'] : "/etc/airtime/airtime.conf";
+			$values = parse_ini_file($airtimeConf, true);
+			
+			$username = $values['database']['dbuser'];
+			$password = $values['database']['dbpass'];
+			$host = $values['database']['host'];
+			$database = $values['database']['dbname'];
+				
+			passthru("export PGPASSWORD=$password && psql -h $host -U $username -q -f $dir/upgrade_sql/airtime_"
+					.$this->getNewVersion()."/upgrade.sql $database 2>&1 | grep -v \"will create implicit index\"");
+			
+			Application_Model_Preference::SetAirtimeVersion($newVersion);
+			Cache::clear();
+			
+			$this->toggleMaintenanceScreen(false);
+			
+			return true;
+		} catch(Exception $e) {
+			$this->toggleMaintenanceScreen(false);
+			throw $e;
+		}
+	}
+}
+
+class AirtimeUpgrader253 extends AirtimeUpgrader
+{
+    protected function getSupportedVersions()
+    {
+        return array('2.5.2');
+    }
+    public function getNewVersion()
+    {
+        return '2.5.3';
+    }
+    
+    public function upgrade($dir = __DIR__)
+    {
+        Cache::clear();
+        assert($this->checkIfUpgradeSupported());
+        
+        $con = Propel::getConnection();
+        $con->beginTransaction();
+        try {
+            
+            $this->toggleMaintenanceScreen(true);
+            Cache::clear();
+            
+            //Begin upgrade
+        
+            //Update disk_usage value in cc_pref
+            $musicDir = CcMusicDirsQuery::create()
+            ->filterByType('stor')
+            ->filterByExists(true)
+            ->findOne();
+            $storPath = $musicDir->getDirectory();
+        
+            //Update disk_usage value in cc_pref
+            $storDir = isset($_SERVER['AIRTIME_BASE']) ? $_SERVER['AIRTIME_BASE']."srv/airtime/stor" : "/srv/airtime/stor";
+            $diskUsage = shell_exec("du -sb $storDir | awk '{print $1}'");
+        
+            Application_Model_Preference::setDiskUsage($diskUsage);
+                    
+            //clear out the cache
+            Cache::clear();
+            
+            $con->commit();
+        
+            //update system_version in cc_pref and change some columns in cc_files
+            $airtimeConf = isset($_SERVER['AIRTIME_CONF']) ? $_SERVER['AIRTIME_CONF'] : "/etc/airtime/airtime.conf";
+            $values = parse_ini_file($airtimeConf, true);
+        
+            $username = $values['database']['dbuser'];
+            $password = $values['database']['dbpass'];
+            $host = $values['database']['host'];
+            $database = $values['database']['dbname'];
+        
+            passthru("export PGPASSWORD=$password && psql -h $host -U $username -q -f $dir/upgrade_sql/airtime_".$this->getNewVersion()."/upgrade.sql $database 2>&1 | grep -v \"will create implicit index\"");
+        
+            Application_Model_Preference::SetAirtimeVersion($this->getNewVersion());
+            //clear out the cache
+            Cache::clear();
+            
+            $this->toggleMaintenanceScreen(false);
+                    
+        } catch (Exception $e) {
+            $con->rollback();
+            $this->toggleMaintenanceScreen(false);
+        }        
+    }
+}
+
+class AirtimeUpgrader254 extends AirtimeUpgrader
+{
+    protected function getSupportedVersions()
+    {
+        return array('2.5.3');
+    }
+    public function getNewVersion()
+    {
+        return '2.5.4';
+    }
+    
+    public function upgrade()
+    {
+        Cache::clear();
+        
+        assert($this->checkIfUpgradeSupported());
+        
+        $newVersion = $this->getNewVersion();
+        
+        $con = Propel::getConnection();
+        //$con->beginTransaction();
+        try {
+            $this->toggleMaintenanceScreen(true);
+            Cache::clear();
+            
+            //Begin upgrade
+
+            //First, ensure there are no superadmins already.
+            $numberOfSuperAdmins = CcSubjsQuery::create()
+            ->filterByDbType(UTYPE_SUPERADMIN)
+            ->filterByDbLogin("sourcefabric_admin", Criteria::NOT_EQUAL) //Ignore sourcefabric_admin users
+            ->count();
+            
+            //Only create a super admin if there isn't one already.
+            if ($numberOfSuperAdmins == 0)
+            {
+                //Find the "admin" user and promote them to superadmin.
+                $adminUser = CcSubjsQuery::create()
+                ->filterByDbLogin('admin')
+                ->findOne();
+                if (!$adminUser)
+                {
+                    //TODO: Otherwise get the user with the lowest ID that is of type administrator:
+                    //
+                    $adminUser = CcSubjsQuery::create()
+                    ->filterByDbType(UTYPE_ADMIN)
+                    ->orderByDbId(Criteria::ASC)
+                    ->findOne();
+                    
+                    if (!$adminUser) {
+                        throw new Exception("Failed to find any users of type 'admin' ('A').");
+                    }
+                }
+                
+                $adminUser = new Application_Model_User($adminUser->getDbId());
+                $adminUser->setType(UTYPE_SUPERADMIN);
+                $adminUser->save();
+                Logging::info($_SERVER['HTTP_HOST'] . ': ' . $newVersion . " Upgrade: Promoted user " . $adminUser->getLogin() . " to be a Super Admin.");
+                
+                //Also try to promote the sourcefabric_admin user
+                $sofabAdminUser = CcSubjsQuery::create()
+                ->filterByDbLogin('sourcefabric_admin')
+                ->findOne();
+                if ($sofabAdminUser) {
+                    $sofabAdminUser = new Application_Model_User($sofabAdminUser->getDbId());
+                    $sofabAdminUser->setType(UTYPE_SUPERADMIN);
+                    $sofabAdminUser->save();
+                    Logging::info($_SERVER['HTTP_HOST'] . ': ' . $newVersion . " Upgrade: Promoted user " . $sofabAdminUser->getLogin() . " to be a Super Admin.");                  
+                }
+            }
+            
+            //$con->commit();
+            Application_Model_Preference::SetAirtimeVersion($newVersion);
+            Cache::clear();
+            
+            $this->toggleMaintenanceScreen(false);
+                        
+            return true;
+            
+        } catch(Exception $e) {
+            //$con->rollback();
+            $this->toggleMaintenanceScreen(false);
+            throw $e; 
+        }
+    }
+}
+
+/* We are skipping 2.5.5 because it used to be the Show Artwork.
+ *
+ * DO NOT USE schema version 2.5.5!
+ */
+
+
+/** This is a stub. Please implement this 2.5.6 upgrader for the next schema change that we need. 
+ *  (It's setup to upgrade from 2.5.4 and 2.5.5 - this is a must due to the 2.5.5 schema being phase out. Long story...
+ *  
+ */ 
+class AirtimeUpgrader256 extends AirtimeUpgrader {
+	protected function getSupportedVersions() {
+		return array (
+                    '2.5.4', '2.5.5'
+		);
+	}
+	
+	public function getNewVersion() {
+		return '2.5.6';
+	}
+	
+	public function upgrade($dir = __DIR__) {
+		Cache::clear();
+		assert($this->checkIfUpgradeSupported());
+		
+		$newVersion = $this->getNewVersion();
+		
+                try {
+                    //TODO: Implement this
+                    return true;
+		} catch(Exception $e) {
+			$this->toggleMaintenanceScreen(false);
+			throw $e;
+		}
+	}
+}
diff --git a/airtime_mvc/build/sql/defaultdata.sql b/airtime_mvc/build/sql/defaultdata.sql
index af82be2b8..94e478fcb 100644
--- a/airtime_mvc/build/sql/defaultdata.sql
+++ b/airtime_mvc/build/sql/defaultdata.sql
@@ -1,3 +1,6 @@
+-- Schema version
+INSERT INTO cc_pref("keystr", "valstr") VALUES('system_version', '2.5.2');
+
 INSERT INTO cc_subjs ("login", "type", "pass") VALUES ('admin', 'A', md5('admin'));
 -- added in 2.3
 INSERT INTO cc_stream_setting ("keyname", "value", "type") VALUES ('off_air_meta', 'Airtime - offline', 'string');