diff --git a/src/Symfony/Component/DependencyInjection/Alias.php b/src/Symfony/Component/DependencyInjection/Alias.php
index 24484de167..2b52986be8 100644
--- a/src/Symfony/Component/DependencyInjection/Alias.php
+++ b/src/Symfony/Component/DependencyInjection/Alias.php
@@ -11,17 +11,24 @@
 
 namespace Symfony\Component\DependencyInjection;
 
+use Symfony\Component\DependencyInjection\Exception\InvalidArgumentException;
+
 class Alias
 {
     private $id;
     private $public;
     private $private;
+    private $deprecated;
+    private $deprecationTemplate;
+
+    private static $defaultDeprecationTemplate = 'The "%service_id%" service alias is deprecated. You should stop using it, as it will soon be removed.';
 
     public function __construct(string $id, bool $public = true)
     {
         $this->id = $id;
         $this->public = $public;
         $this->private = 2 > \func_num_args();
+        $this->deprecated = false;
     }
 
     /**
@@ -78,6 +85,58 @@ class Alias
         return $this->private;
     }
 
+    /**
+     * Whether this alias is deprecated, that means it should not be called
+     * anymore.
+     *
+     * @param bool   $status   Defaults to true
+     * @param string $template Optional template message to use if the alias is deprecated
+     *
+     * @return $this
+     *
+     * @throws InvalidArgumentException when the message template is invalid
+     */
+    public function setDeprecated($status = true, $template = null)
+    {
+        if (null !== $template) {
+            if (preg_match('#[\r\n]|\*/#', $template)) {
+                throw new InvalidArgumentException('Invalid characters found in deprecation template.');
+            }
+
+            if (false === strpos($template, '%service_id%')) {
+                throw new InvalidArgumentException('The deprecation template must contain the "%service_id%" placeholder.');
+            }
+
+            $this->deprecationTemplate = $template;
+        }
+
+        $this->deprecated = (bool) $status;
+
+        return $this;
+    }
+
+    /**
+     * Returns whether this alias is deprecated.
+     *
+     * @return bool
+     */
+    public function isDeprecated()
+    {
+        return $this->deprecated;
+    }
+
+    /**
+     * Message to use if this alias is deprecated.
+     *
+     * @param string $id Service id relying on this alias
+     *
+     * @return string
+     */
+    public function getDeprecationMessage($id)
+    {
+        return str_replace('%service_id%', $id, $this->deprecationTemplate ?: self::$defaultDeprecationTemplate);
+    }
+
     /**
      * Returns the Id of this alias.
      *
diff --git a/src/Symfony/Component/DependencyInjection/ContainerBuilder.php b/src/Symfony/Component/DependencyInjection/ContainerBuilder.php
index 58a4bfc484..999410fb2d 100644
--- a/src/Symfony/Component/DependencyInjection/ContainerBuilder.php
+++ b/src/Symfony/Component/DependencyInjection/ContainerBuilder.php
@@ -579,7 +579,12 @@ class ContainerBuilder extends Container implements TaggedContainerInterface
         }
 
         if (!isset($this->definitions[$id]) && isset($this->aliasDefinitions[$id])) {
-            return $this->doGet((string) $this->aliasDefinitions[$id], $invalidBehavior, $inlineServices, $isConstructorArgument);
+            $aliasDefinition = $this->aliasDefinitions[$id];
+            if ($aliasDefinition->isDeprecated()) {
+                @trigger_error($aliasDefinition->getDeprecationMessage($id), E_USER_DEPRECATED);
+            }
+
+            return $this->doGet((string) $aliasDefinition, $invalidBehavior, $inlineServices, $isConstructorArgument);
         }
 
         try {
diff --git a/src/Symfony/Component/DependencyInjection/Loader/XmlFileLoader.php b/src/Symfony/Component/DependencyInjection/Loader/XmlFileLoader.php
index c5292ecf68..61b30a22e4 100644
--- a/src/Symfony/Component/DependencyInjection/Loader/XmlFileLoader.php
+++ b/src/Symfony/Component/DependencyInjection/Loader/XmlFileLoader.php
@@ -220,6 +220,10 @@ class XmlFileLoader extends FileLoader
                 $alias->setPublic($defaults['public']);
             }
 
+            if ($deprecated = $this->getChildren($service, 'deprecated')) {
+                $alias->setDeprecated(true, $deprecated[0]->nodeValue ?: null);
+            }
+
             return;
         }
 
@@ -667,8 +671,12 @@ EOF
             }
         }
 
+        $allowedTags = array('deprecated');
         foreach ($alias->childNodes as $child) {
-            if ($child instanceof \DOMElement && self::NS === $child->namespaceURI) {
+            if (!$child instanceof \DOMElement && self::NS !== $child->namespaceURI) {
+                continue;
+            }
+            if (!in_array($child->localName, $allowedTags, true)) {
                 throw new InvalidArgumentException(sprintf('Invalid child element "%s" defined for alias "%s" in "%s".', $child->localName, $alias->getAttribute('id'), $file));
             }
         }
diff --git a/src/Symfony/Component/DependencyInjection/Loader/YamlFileLoader.php b/src/Symfony/Component/DependencyInjection/Loader/YamlFileLoader.php
index 05fbe86363..13d6746c10 100644
--- a/src/Symfony/Component/DependencyInjection/Loader/YamlFileLoader.php
+++ b/src/Symfony/Component/DependencyInjection/Loader/YamlFileLoader.php
@@ -349,8 +349,13 @@ class YamlFileLoader extends FileLoader
             }
 
             foreach ($service as $key => $value) {
-                if (!\in_array($key, ['alias', 'public'])) {
+                if (!\in_array($key, ['alias', 'public', 'deprecated'])) {
                     throw new InvalidArgumentException(sprintf('The configuration key "%s" is unsupported for the service "%s" which is defined as an alias in "%s". Allowed configuration keys for service aliases are "alias" and "public".', $key, $id, $file));
+                    continue;
+                }
+
+                if ('deprecated' === $key) {
+                    $alias->setDeprecated(true, $value);
                 }
             }
 
diff --git a/src/Symfony/Component/DependencyInjection/Tests/AliasTest.php b/src/Symfony/Component/DependencyInjection/Tests/AliasTest.php
new file mode 100644
index 0000000000..eb61a9df7d
--- /dev/null
+++ b/src/Symfony/Component/DependencyInjection/Tests/AliasTest.php
@@ -0,0 +1,110 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\DependencyInjection\Tests;
+
+use PHPUnit\Framework\TestCase;
+use Symfony\Component\DependencyInjection\Alias;
+
+class AliasTest extends TestCase
+{
+    public function testConstructor()
+    {
+        $alias = new Alias('foo');
+
+        $this->assertEquals('foo', (string) $alias);
+        $this->assertTrue($alias->isPublic());
+    }
+
+    public function testCanConstructANonPublicAlias()
+    {
+        $alias = new Alias('foo', false);
+
+        $this->assertEquals('foo', (string) $alias);
+        $this->assertFalse($alias->isPublic());
+    }
+
+    public function testCanConstructAPrivateAlias()
+    {
+        $alias = new Alias('foo', false, false);
+
+        $this->assertEquals('foo', (string) $alias);
+        $this->assertFalse($alias->isPublic());
+        $this->assertFalse($alias->isPrivate());
+    }
+
+    public function testCanSetPublic()
+    {
+        $alias = new Alias('foo', false);
+        $alias->setPublic(true);
+
+        $this->assertTrue($alias->isPublic());
+    }
+
+    public function testCanDeprecateAnAlias()
+    {
+        $alias = new Alias('foo', false);
+        $alias->setDeprecated(true, 'The %service_id% service is deprecated.');
+
+        $this->assertTrue($alias->isDeprecated());
+    }
+
+    public function testItHasADefaultDeprecationMessage()
+    {
+        $alias = new Alias('foo', false);
+        $alias->setDeprecated();
+
+        $expectedMessage = 'The "foo" service alias is deprecated. You should stop using it, as it will soon be removed.';
+        $this->assertEquals($expectedMessage, $alias->getDeprecationMessage('foo'));
+    }
+
+    public function testReturnsCorrectDeprecationMessage()
+    {
+        $alias = new Alias('foo', false);
+        $alias->setDeprecated(true, 'The "%service_id%" is deprecated.');
+
+        $expectedMessage = 'The "foo" is deprecated.';
+        $this->assertEquals($expectedMessage, $alias->getDeprecationMessage('foo'));
+    }
+
+    public function testCanOverrideDeprecation()
+    {
+        $alias = new Alias('foo', false);
+        $alias->setDeprecated();
+
+        $initial = $alias->isDeprecated();
+        $alias->setDeprecated(false);
+        $final = $alias->isDeprecated();
+
+        $this->assertTrue($initial);
+        $this->assertFalse($final);
+    }
+
+    /**
+     * @dataProvider invalidDeprecationMessageProvider
+     * @expectedException \Symfony\Component\DependencyInjection\Exception\InvalidArgumentException
+     */
+    public function testCannotDeprecateWithAnInvalidTemplate($message)
+    {
+        $def = new Alias('foo');
+        $def->setDeprecated(true, $message);
+    }
+
+    public function invalidDeprecationMessageProvider()
+    {
+        return array(
+            "With \rs" => array("invalid \r message %service_id%"),
+            "With \ns" => array("invalid \n message %service_id%"),
+            'With */s' => array('invalid */ message %service_id%'),
+            'message not containing required %service_id% variable' => array('this is deprecated'),
+        );
+    }
+}
diff --git a/src/Symfony/Component/DependencyInjection/Tests/ContainerBuilderTest.php b/src/Symfony/Component/DependencyInjection/Tests/ContainerBuilderTest.php
index 83c0458e5c..cec7ea4d18 100644
--- a/src/Symfony/Component/DependencyInjection/Tests/ContainerBuilderTest.php
+++ b/src/Symfony/Component/DependencyInjection/Tests/ContainerBuilderTest.php
@@ -259,6 +259,22 @@ class ContainerBuilderTest extends TestCase
         }
     }
 
+    /**
+     * @group legacy
+     * @expectedDeprecation The "foobar" service alias is deprecated. You should stop using it, as it will soon be removed.
+     */
+    public function testDeprecatedAlias()
+    {
+        $builder = new ContainerBuilder();
+        $builder->register('foo', 'stdClass');
+
+        $alias = new Alias('foo');
+        $alias->setDeprecated();
+        $builder->setAlias('foobar', $alias);
+
+        $builder->get('foobar');
+    }
+
     public function testGetAliases()
     {
         $builder = new ContainerBuilder();
diff --git a/src/Symfony/Component/DependencyInjection/Tests/Fixtures/xml/deprecated_alias_definitions.xml b/src/Symfony/Component/DependencyInjection/Tests/Fixtures/xml/deprecated_alias_definitions.xml
new file mode 100644
index 0000000000..83ceeefa9c
--- /dev/null
+++ b/src/Symfony/Component/DependencyInjection/Tests/Fixtures/xml/deprecated_alias_definitions.xml
@@ -0,0 +1,13 @@
+<?xml version="1.0" encoding="utf-8"?>
+<container xmlns="http://symfony.com/schema/dic/services" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://symfony.com/schema/dic/services http://symfony.com/schema/dic/services/services-1.0.xsd">
+  <services>
+    <service id="foo" class="Foo">
+    </service>
+    <service id="alias_for_foo" alias="foo">
+      <deprecated />
+    </service>
+    <service id="alias_for_foobar" alias="foobar">
+      <deprecated>The "%service_id%" service alias is deprecated.</deprecated>
+    </service>
+  </services>
+</container>
diff --git a/src/Symfony/Component/DependencyInjection/Tests/Fixtures/yaml/deprecated_alias_definitions.yml b/src/Symfony/Component/DependencyInjection/Tests/Fixtures/yaml/deprecated_alias_definitions.yml
new file mode 100644
index 0000000000..2223597815
--- /dev/null
+++ b/src/Symfony/Component/DependencyInjection/Tests/Fixtures/yaml/deprecated_alias_definitions.yml
@@ -0,0 +1,4 @@
+services:
+    alias_for_foobar:
+        alias: foobar
+        deprecated: The "%service_id%" service alias is deprecated.
diff --git a/src/Symfony/Component/DependencyInjection/Tests/Loader/XmlFileLoaderTest.php b/src/Symfony/Component/DependencyInjection/Tests/Loader/XmlFileLoaderTest.php
index 6d9634c66c..e5037d809b 100644
--- a/src/Symfony/Component/DependencyInjection/Tests/Loader/XmlFileLoaderTest.php
+++ b/src/Symfony/Component/DependencyInjection/Tests/Loader/XmlFileLoaderTest.php
@@ -351,6 +351,21 @@ class XmlFileLoaderTest extends TestCase
         $this->assertSame($message, $container->getDefinition('bar')->getDeprecationMessage('bar'));
     }
 
+    public function testDeprecatedAliases()
+    {
+        $container = new ContainerBuilder();
+        $loader = new XmlFileLoader($container, new FileLocator(self::$fixturesPath.'/xml'));
+        $loader->load('deprecated_alias_definitions.xml');
+
+        $this->assertTrue($container->getAlias('alias_for_foo')->isDeprecated());
+        $message = 'The "alias_for_foo" service alias is deprecated. You should stop using it, as it will soon be removed.';
+        $this->assertSame($message, $container->getAlias('alias_for_foo')->getDeprecationMessage('alias_for_foo'));
+
+        $this->assertTrue($container->getAlias('alias_for_foobar')->isDeprecated());
+        $message = 'The "alias_for_foobar" service alias is deprecated.';
+        $this->assertSame($message, $container->getAlias('alias_for_foobar')->getDeprecationMessage('alias_for_foobar'));
+    }
+
     public function testConvertDomElementToArray()
     {
         $doc = new \DOMDocument('1.0');
diff --git a/src/Symfony/Component/DependencyInjection/Tests/Loader/YamlFileLoaderTest.php b/src/Symfony/Component/DependencyInjection/Tests/Loader/YamlFileLoaderTest.php
index 37e6054f55..8c9ccaf06f 100644
--- a/src/Symfony/Component/DependencyInjection/Tests/Loader/YamlFileLoaderTest.php
+++ b/src/Symfony/Component/DependencyInjection/Tests/Loader/YamlFileLoaderTest.php
@@ -175,6 +175,17 @@ class YamlFileLoaderTest extends TestCase
         $this->assertEquals(['decorated', 'decorated.pif-pouf', 5], $services['decorator_service_with_name_and_priority']->getDecoratedService());
     }
 
+    public function testDeprecatedAliases()
+    {
+        $container = new ContainerBuilder();
+        $loader = new YamlFileLoader($container, new FileLocator(self::$fixturesPath.'/yaml'));
+        $loader->load('deprecated_alias_definitions.yml');
+
+        $this->assertTrue($container->getAlias('alias_for_foobar')->isDeprecated());
+        $message = 'The "alias_for_foobar" service alias is deprecated.';
+        $this->assertSame($message, $container->getAlias('alias_for_foobar')->getDeprecationMessage('alias_for_foobar'));
+    }
+
     public function testLoadFactoryShortSyntax()
     {
         $container = new ContainerBuilder();