diff --git a/src/Composer/Downloader/GitDownloader.php b/src/Composer/Downloader/GitDownloader.php
index ebb546a96..54cdd4240 100644
--- a/src/Composer/Downloader/GitDownloader.php
+++ b/src/Composer/Downloader/GitDownloader.php
@@ -13,13 +13,20 @@
 namespace Composer\Downloader;
 
 use Composer\Package\PackageInterface;
-use Composer\Util\Process;
+use Composer\Util\ProcessExecutor;
 
 /**
  * @author Jordi Boggiano <j.boggiano@seld.be>
  */
 class GitDownloader implements DownloaderInterface
 {
+    protected $process;
+
+    public function __construct(ProcessExecutor $process = null)
+    {
+        $this->process = $process ?: new ProcessExecutor;
+    }
+
     /**
      * {@inheritDoc}
      */
@@ -39,7 +46,7 @@ class GitDownloader implements DownloaderInterface
 
         $url = escapeshellarg($package->getSourceUrl());
         $ref = escapeshellarg($package->getSourceReference());
-        Process::execute(sprintf('git clone %s %s && cd %2$s && git checkout %3$s && git reset --hard %3$s', $url, $path, $ref));
+        $this->process->execute(sprintf('git clone %s %s && cd %2$s && git checkout %3$s && git reset --hard %3$s', $url, $path, $ref));
     }
 
     /**
@@ -52,7 +59,7 @@ class GitDownloader implements DownloaderInterface
         }
 
         $this->enforceCleanDirectory($path);
-        Process::execute(sprintf('cd %s && git fetch && git checkout %2$s && git reset --hard %2$s', $path, $target->getSourceReference()));
+        $this->process->execute(sprintf('cd %s && git fetch && git checkout %2$s && git reset --hard %2$s', $path, $target->getSourceReference()));
     }
 
     /**
@@ -67,7 +74,7 @@ class GitDownloader implements DownloaderInterface
 
     private function enforceCleanDirectory($path)
     {
-        Process::execute(sprintf('cd %s && git status --porcelain', $path),$output);
+        $this->process->execute(sprintf('cd %s && git status --porcelain', $path),$output);
         if (implode('', $output)) {
             throw new \RuntimeException('Source directory has uncommitted changes');
         }
diff --git a/src/Composer/Downloader/HgDownloader.php b/src/Composer/Downloader/HgDownloader.php
index b7d7fbbe0..d45711228 100644
--- a/src/Composer/Downloader/HgDownloader.php
+++ b/src/Composer/Downloader/HgDownloader.php
@@ -13,13 +13,20 @@
 namespace Composer\Downloader;
 
 use Composer\Package\PackageInterface;
-use Composer\Util\Process;
+use Composer\Util\ProcessExecutor;
 
 /**
  * @author Per Bernhardt <plb@webfactory.de>
  */
 class HgDownloader implements DownloaderInterface
 {
+    protected $process;
+
+    public function __construct(ProcessExecutor $process = null)
+    {
+        $this->process = $process ?: new ProcessExecutor;
+    }
+
     /**
      * {@inheritDoc}
      */
@@ -39,7 +46,7 @@ class HgDownloader implements DownloaderInterface
 
         $url = escapeshellarg($package->getSourceUrl());
         $ref = escapeshellarg($package->getSourceReference());
-        Process::execute(sprintf('(hg clone %s %s  2> /dev/null) && cd %2$s && hg up %s', $url, $path, $ref));
+        $this->process->execute(sprintf('(hg clone %s %s  2> /dev/null) && cd %2$s && hg up %s', $url, $path, $ref));
     }
 
     /**
@@ -52,7 +59,7 @@ class HgDownloader implements DownloaderInterface
         }
 
         $this->enforceCleanDirectory($path);
-        Process::execute(sprintf('cd %s && hg pull && hg up %s', $path, escapeshellarg($target->getSourceReference())));
+        $this->process->execute(sprintf('cd %s && hg pull && hg up %s', $path, escapeshellarg($target->getSourceReference())));
     }
 
     /**
@@ -67,7 +74,7 @@ class HgDownloader implements DownloaderInterface
 
     private function enforceCleanDirectory($path)
     {
-        Process::execute(sprintf('cd %s && hg st', $path), $output);
+        $this->process->execute(sprintf('cd %s && hg st', $path), $output);
         if (implode('', $output)) {
             throw new \RuntimeException('Source directory has uncommitted changes');
         }
diff --git a/src/Composer/Downloader/SvnDownloader.php b/src/Composer/Downloader/SvnDownloader.php
index d6577a0b1..7661760bb 100644
--- a/src/Composer/Downloader/SvnDownloader.php
+++ b/src/Composer/Downloader/SvnDownloader.php
@@ -1,15 +1,32 @@
 <?php
 
+/*
+ * This file is part of Composer.
+ *
+ * (c) Nils Adermann <naderman@naderman.de>
+ *     Jordi Boggiano <j.boggiano@seld.be>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
 namespace Composer\Downloader;
 
 use Composer\Package\PackageInterface;
-use Composer\Util\Process;
+use Composer\Util\ProcessExecutor;
 
 /**
  * @author Ben Bieker <mail@ben-bieker.de>
  */
 class SvnDownloader implements DownloaderInterface
 {
+    protected $process;
+
+    public function __construct(ProcessExecutor $process = null)
+    {
+        $this->process = $process ?: new ProcessExecutor;
+    }
+
     /**
      * {@inheritDoc}
      */
@@ -29,7 +46,7 @@ class SvnDownloader implements DownloaderInterface
 
         $url = escapeshellarg($package->getSourceUrl());
         $ref = escapeshellarg($package->getSourceReference());
-        Process::execute(sprintf('svn co %s/%s %s', $url, $ref, $path));
+        $this->process->execute(sprintf('svn co %s/%s %s', $url, $ref, $path));
     }
 
     /**
@@ -43,7 +60,7 @@ class SvnDownloader implements DownloaderInterface
 
         $url = escapeshellarg($target->getSourceUrl());
         $ref = escapeshellarg($target->getSourceReference());
-        Process::execute(sprintf('cd %s && svn switch %s/%s', $path, $url, $ref));
+        $this->process->execute(sprintf('cd %s && svn switch %s/%s', $path, $url, $ref));
     }
 
     /**
diff --git a/src/Composer/Downloader/Util/Filesystem.php b/src/Composer/Downloader/Util/Filesystem.php
index 6e73faa63..6d044e40e 100644
--- a/src/Composer/Downloader/Util/Filesystem.php
+++ b/src/Composer/Downloader/Util/Filesystem.php
@@ -12,7 +12,7 @@
 
 namespace Composer\Downloader\Util;
 
-use Composer\Util\Process;
+use Composer\Util\ProcessExecutor;
 
 /**
  * @author Jordi Boggiano <j.boggiano@seld.be>
@@ -22,10 +22,12 @@ class Filesystem
     public function removeDirectory($directory)
     {
         if (defined('PHP_WINDOWS_VERSION_BUILD')) {
-            Process::execute(sprintf('rmdir /S /Q %s', escapeshellarg(realpath($directory))));
+            $cmd = sprintf('rmdir /S /Q %s', escapeshellarg(realpath($directory)));
         } else {
-            Process::execute(sprintf('rm -rf %s', escapeshellarg($directory)));
+            $cmd = sprintf('rm -rf %s', escapeshellarg($directory));
         }
+
+        return $this->getProcess()->execute($cmd) === 0;
     }
 
     public function ensureDirectoryExists($directory)
@@ -127,4 +129,9 @@ class Filesystem
     {
         return substr($path, 0, 1) === '/' || substr($path, 1, 1) === ':';
     }
+
+    protected function getProcess()
+    {
+        return new ProcessExecutor;
+    }
 }
\ No newline at end of file
diff --git a/src/Composer/Repository/Vcs/GitDriver.php b/src/Composer/Repository/Vcs/GitDriver.php
index 9d74d1a73..2ca0bf90d 100644
--- a/src/Composer/Repository/Vcs/GitDriver.php
+++ b/src/Composer/Repository/Vcs/GitDriver.php
@@ -3,7 +3,7 @@
 namespace Composer\Repository\Vcs;
 
 use Composer\Json\JsonFile;
-use Composer\Util\Process;
+use Composer\Util\ProcessExecutor;
 use Composer\IO\IOInterface;
 
 /**
@@ -16,11 +16,11 @@ class GitDriver extends VcsDriver implements VcsDriverInterface
     protected $rootIdentifier;
     protected $infoCache = array();
 
-    public function __construct($url, IOInterface $io)
+    public function __construct($url, IOInterface $io, ProcessExecutor $process = null)
     {
         $this->tmpDir = sys_get_temp_dir() . '/composer-' . preg_replace('{[^a-z0-9]}i', '-', $url) . '/';
 
-        parent::__construct($url, $io);
+        parent::__construct($url, $io, $process);
     }
 
     /**
@@ -31,9 +31,9 @@ class GitDriver extends VcsDriver implements VcsDriverInterface
         $url = escapeshellarg($this->url);
         $tmpDir = escapeshellarg($this->tmpDir);
         if (is_dir($this->tmpDir)) {
-            Process::execute(sprintf('cd %s && git fetch origin', $tmpDir), $output);
+            $this->process->execute(sprintf('cd %s && git fetch origin', $tmpDir), $output);
         } else {
-            Process::execute(sprintf('git clone %s %s', $url, $tmpDir), $output);
+            $this->process->execute(sprintf('git clone %s %s', $url, $tmpDir), $output);
         }
 
         $this->getTags();
@@ -47,7 +47,7 @@ class GitDriver extends VcsDriver implements VcsDriverInterface
     {
         if (null === $this->rootIdentifier) {
             $this->rootIdentifier = 'master';
-            Process::execute(sprintf('cd %s && git branch --no-color -r', escapeshellarg($this->tmpDir)), $output);
+            $this->process->execute(sprintf('cd %s && git branch --no-color -r', escapeshellarg($this->tmpDir)), $output);
             foreach ($output as $branch) {
                 if ($branch && preg_match('{/HEAD +-> +[^/]+/(\S+)}', $branch, $match)) {
                     $this->rootIdentifier = $match[1];
@@ -91,7 +91,7 @@ class GitDriver extends VcsDriver implements VcsDriverInterface
     public function getComposerInformation($identifier)
     {
         if (!isset($this->infoCache[$identifier])) {
-            Process::execute(sprintf('cd %s && git show %s:composer.json', escapeshellarg($this->tmpDir), escapeshellarg($identifier)), $output);
+            $this->process->execute(sprintf('cd %s && git show %s:composer.json', escapeshellarg($this->tmpDir), escapeshellarg($identifier)), $output);
             $composer = implode("\n", $output);
             unset($output);
 
@@ -102,7 +102,7 @@ class GitDriver extends VcsDriver implements VcsDriverInterface
             $composer = JsonFile::parseJson($composer);
 
             if (!isset($composer['time'])) {
-                Process::execute(sprintf('cd %s && git log -1 --format=%%at %s', escapeshellarg($this->tmpDir), escapeshellarg($identifier)), $output);
+                $this->process->execute(sprintf('cd %s && git log -1 --format=%%at %s', escapeshellarg($this->tmpDir), escapeshellarg($identifier)), $output);
                 $date = new \DateTime('@'.$output[0]);
                 $composer['time'] = $date->format('Y-m-d H:i:s');
             }
@@ -118,7 +118,7 @@ class GitDriver extends VcsDriver implements VcsDriverInterface
     public function getTags()
     {
         if (null === $this->tags) {
-            Process::execute(sprintf('cd %s && git tag', escapeshellarg($this->tmpDir)), $output);
+            $this->process->execute(sprintf('cd %s && git tag', escapeshellarg($this->tmpDir)), $output);
             $this->tags = $output ? array_combine($output, $output) : array();
         }
 
@@ -133,7 +133,7 @@ class GitDriver extends VcsDriver implements VcsDriverInterface
         if (null === $this->branches) {
             $branches = array();
 
-            Process::execute(sprintf('cd %s && git branch --no-color -rv', escapeshellarg($this->tmpDir)), $output);
+            $this->process->execute(sprintf('cd %s && git branch --no-color -rv', escapeshellarg($this->tmpDir)), $output);
             foreach ($output as $branch) {
                 if ($branch && !preg_match('{^ *[^/]+/HEAD }', $branch)) {
                     preg_match('{^ *[^/]+/(\S+) *([a-f0-9]+) .*$}', $branch, $match);
diff --git a/src/Composer/Repository/Vcs/HgDriver.php b/src/Composer/Repository/Vcs/HgDriver.php
index e66fc0a6f..e458eb499 100644
--- a/src/Composer/Repository/Vcs/HgDriver.php
+++ b/src/Composer/Repository/Vcs/HgDriver.php
@@ -13,7 +13,7 @@
 namespace Composer\Repository\Vcs;
 
 use Composer\Json\JsonFile;
-use Composer\Util\Process;
+use Composer\Util\ProcessExecutor;
 use Composer\IO\IOInterface;
 
 /**
@@ -26,11 +26,11 @@ class HgDriver extends VcsDriver implements VcsDriverInterface
     protected $rootIdentifier;
     protected $infoCache = array();
 
-    public function __construct($url, IOInterface $io)
+    public function __construct($url, IOInterface $io, ProcessExecutor $process = null)
     {
         $this->tmpDir = sys_get_temp_dir() . '/composer-' . preg_replace('{[^a-z0-9]}i', '-', $url) . '/';
 
-        parent::__construct($url, $io);
+        parent::__construct($url, $io, $process);
     }
 
     /**
@@ -41,9 +41,9 @@ class HgDriver extends VcsDriver implements VcsDriverInterface
         $url = escapeshellarg($this->url);
         $tmpDir = escapeshellarg($this->tmpDir);
         if (is_dir($this->tmpDir)) {
-            Process::execute(sprintf('cd %s && hg pull -u', $tmpDir), $output);
+            $this->process->execute(sprintf('cd %s && hg pull -u', $tmpDir), $output);
         } else {
-            Process::execute(sprintf('cd %s && hg clone %s %s', escapeshellarg(sys_get_temp_dir()), $url, $tmpDir), $output);
+            $this->process->execute(sprintf('cd %s && hg clone %s %s', escapeshellarg(sys_get_temp_dir()), $url, $tmpDir), $output);
         }
 
         $this->getTags();
@@ -57,7 +57,7 @@ class HgDriver extends VcsDriver implements VcsDriverInterface
     {
         $tmpDir = escapeshellarg($this->tmpDir);
         if (null === $this->rootIdentifier) {
-            Process::execute(sprintf('cd %s && hg tip --template "{node}"', $tmpDir), $output);
+            $this->process->execute(sprintf('cd %s && hg tip --template "{node}"', $tmpDir), $output);
             $this->rootIdentifier = $output[0];
         }
 
@@ -96,7 +96,7 @@ class HgDriver extends VcsDriver implements VcsDriverInterface
     public function getComposerInformation($identifier)
     {
         if (!isset($this->infoCache[$identifier])) {
-            Process::execute(sprintf('cd %s && hg cat -r %s composer.json', escapeshellarg($this->tmpDir), escapeshellarg($identifier)), $output);
+            $this->process->execute(sprintf('cd %s && hg cat -r %s composer.json', escapeshellarg($this->tmpDir), escapeshellarg($identifier)), $output);
             $composer = implode("\n", $output);
             unset($output);
 
@@ -107,7 +107,7 @@ class HgDriver extends VcsDriver implements VcsDriverInterface
             $composer = JsonFile::parseJson($composer);
 
             if (!isset($composer['time'])) {
-                Process::execute(sprintf('cd %s && hg log --template "{date|rfc822date}" -r %s', escapeshellarg($this->tmpDir), escapeshellarg($identifier)), $output);
+                $this->process->execute(sprintf('cd %s && hg log --template "{date|rfc822date}" -r %s', escapeshellarg($this->tmpDir), escapeshellarg($identifier)), $output);
                 $date = new \DateTime($output[0]);
                 $composer['time'] = $date->format('Y-m-d H:i:s');
             }
@@ -125,7 +125,7 @@ class HgDriver extends VcsDriver implements VcsDriverInterface
         if (null === $this->tags) {
             $tags = array();
 
-            Process::execute(sprintf('cd %s && hg tags', escapeshellarg($this->tmpDir)), $output);
+            $this->process->execute(sprintf('cd %s && hg tags', escapeshellarg($this->tmpDir)), $output);
             foreach ($output as $tag) {
                 if (preg_match('(^([^\s]+)\s+\d+:(.*)$)', $tag, $match))
                     $tags[$match[1]] = $match[2];
@@ -145,7 +145,7 @@ class HgDriver extends VcsDriver implements VcsDriverInterface
         if (null === $this->branches) {
             $branches = array();
 
-            Process::execute(sprintf('cd %s && hg branches', escapeshellarg($this->tmpDir)), $output);
+            $this->process->execute(sprintf('cd %s && hg branches', escapeshellarg($this->tmpDir)), $output);
             foreach ($output as $branch) {
                 if (preg_match('(^([^\s]+)\s+\d+:(.*)$)', $branch, $match))
                     $branches[$match[1]] = $match[2];
@@ -184,7 +184,7 @@ class HgDriver extends VcsDriver implements VcsDriverInterface
             return false;
         }
 
-        $exit = Process::execute(sprintf('cd %s && hg identify %s', escapeshellarg(sys_get_temp_dir()), escapeshellarg($url)), $ignored);
+        $exit = $this->process->execute(sprintf('cd %s && hg identify %s', escapeshellarg(sys_get_temp_dir()), escapeshellarg($url)), $ignored);
         return $exit === 0;
     }
 }
diff --git a/src/Composer/Repository/Vcs/SvnDriver.php b/src/Composer/Repository/Vcs/SvnDriver.php
index 9ff3ba613..ad28080a0 100644
--- a/src/Composer/Repository/Vcs/SvnDriver.php
+++ b/src/Composer/Repository/Vcs/SvnDriver.php
@@ -3,7 +3,7 @@
 namespace Composer\Repository\Vcs;
 
 use Composer\Json\JsonFile;
-use Composer\Util\Process;
+use Composer\Util\ProcessExecutor;
 use Composer\IO\IOInterface;
 
 /**
@@ -16,9 +16,9 @@ class SvnDriver extends VcsDriver implements VcsDriverInterface
     protected $branches;
     protected $infoCache = array();
 
-    public function __construct($url, IOInterface $io)
+    public function __construct($url, IOInterface $io, ProcessExecutor $process = null)
     {
-        parent::__construct($this->baseUrl = rtrim($url, '/'), $io);
+        parent::__construct($this->baseUrl = rtrim($url, '/'), $io, $process);
 
         if (false !== ($pos = strrpos($url, '/trunk'))) {
             $this->baseUrl = substr($url, 0, $pos);
@@ -80,7 +80,7 @@ class SvnDriver extends VcsDriver implements VcsDriverInterface
                 $rev = '';
             }
 
-            Process::execute(sprintf('svn cat --non-interactive %s', escapeshellarg($this->baseUrl.$identifier.'composer.json'.$rev)),$output);
+            $this->process->execute(sprintf('svn cat --non-interactive %s', escapeshellarg($this->baseUrl.$identifier.'composer.json'.$rev)),$output);
             $composer = implode("\n", $output);
             unset($output);
 
@@ -91,7 +91,7 @@ class SvnDriver extends VcsDriver implements VcsDriverInterface
             $composer = JsonFile::parseJson($composer);
 
             if (!isset($composer['time'])) {
-                Process::execute(sprintf('svn info %s', escapeshellarg($this->baseUrl.$identifier.$rev)), $output);
+                $this->process->execute(sprintf('svn info %s', escapeshellarg($this->baseUrl.$identifier.$rev)), $output);
                 foreach ($output as $line) {
                     if (preg_match('{^Last Changed Date: ([^(]+)}', $line, $match)) {
                         $date = new \DateTime($match[1]);
@@ -112,7 +112,7 @@ class SvnDriver extends VcsDriver implements VcsDriverInterface
     public function getTags()
     {
         if (null === $this->tags) {
-            Process::execute(sprintf('svn ls --non-interactive %s', escapeshellarg($this->baseUrl.'/tags')), $output);
+            $this->process->execute(sprintf('svn ls --non-interactive %s', escapeshellarg($this->baseUrl.'/tags')), $output);
             $this->tags = array();
             foreach ($output as $tag) {
                 $this->tags[rtrim($tag, '/')] = '/tags/'.$tag;
@@ -128,7 +128,7 @@ class SvnDriver extends VcsDriver implements VcsDriverInterface
     public function getBranches()
     {
         if (null === $this->branches) {
-            Process::execute(sprintf('svn ls --verbose --non-interactive %s', escapeshellarg($this->baseUrl.'/')), $output);
+            $this->process->execute(sprintf('svn ls --verbose --non-interactive %s', escapeshellarg($this->baseUrl.'/')), $output);
 
             $this->branches = array();
             foreach ($output as $line) {
@@ -140,7 +140,7 @@ class SvnDriver extends VcsDriver implements VcsDriverInterface
             }
             unset($output);
 
-            Process::execute(sprintf('svn ls --verbose --non-interactive %s', escapeshellarg($this->baseUrl.'/branches')), $output);
+            $this->process->execute(sprintf('svn ls --verbose --non-interactive %s', escapeshellarg($this->baseUrl.'/branches')), $output);
             foreach ($output as $line) {
                 preg_match('{^\s*(\S+).*?(\S+)\s*$}', $line, $match);
                 if ($match[2] === './') {
@@ -180,7 +180,7 @@ class SvnDriver extends VcsDriver implements VcsDriverInterface
             return false;
         }
 
-        $exit = Process::execute(sprintf('svn info --non-interactive %s 2>/dev/null', escapeshellarg($url)), $ignored);
+        $exit = $this->process->execute(sprintf('svn info --non-interactive %s 2>/dev/null', escapeshellarg($url)), $ignored);
         return $exit === 0;
     }
 }
diff --git a/src/Composer/Repository/Vcs/VcsDriver.php b/src/Composer/Repository/Vcs/VcsDriver.php
index 62d69b324..cf7af1fa9 100644
--- a/src/Composer/Repository/Vcs/VcsDriver.php
+++ b/src/Composer/Repository/Vcs/VcsDriver.php
@@ -13,6 +13,7 @@
 namespace Composer\Repository\Vcs;
 
 use Composer\IO\IOInterface;
+use Composer\Util\ProcessExecutor;
 
 /**
  * A driver implementation for driver with authorization interaction.
@@ -23,6 +24,7 @@ abstract class VcsDriver
 {
     protected $url;
     protected $io;
+    protected $process;
     private $firstCall;
     private $contentUrl;
     private $content;
@@ -32,11 +34,13 @@ abstract class VcsDriver
      *
      * @param string      $url The URL
      * @param IOInterface $io  The IO instance
+     * @param ProcessExecutor $process  Process instance, injectable for mocking
      */
-    public function __construct($url, IOInterface $io)
+    public function __construct($url, IOInterface $io, ProcessExecutor $process = null)
     {
         $this->url = $url;
         $this->io = $io;
+        $this->process = $process ?: new ProcessExecutor;
         $this->firstCall = true;
     }
 
diff --git a/src/Composer/Util/Process.php b/src/Composer/Util/ProcessExecutor.php
similarity index 81%
rename from src/Composer/Util/Process.php
rename to src/Composer/Util/ProcessExecutor.php
index 1a34b0ea7..08bcc1e0e 100644
--- a/src/Composer/Util/Process.php
+++ b/src/Composer/Util/ProcessExecutor.php
@@ -12,24 +12,23 @@
 
 namespace Composer\Util;
 
-use Symfony\Component\Process\Process as BaseProcess;
+use Symfony\Component\Process\Process;
 
 /**
  * @author Robert Schönthal <seroscho@googlemail.com>
  */
-class Process extends BaseProcess
+class ProcessExecutor
 {
     /**
      * runs a process on the commandline
      *
-     * @static
      * @param $command the command to execute
      * @param null $output the output will be written into this var if passed
      * @return int statuscode
      */
-    public static function execute($command, &$output = null)
+    public function execute($command, &$output = null)
     {
-        $process = new static($command);
+        $process = new Process($command);
         $process->run(function($type, $buffer) use ($output) {
             if (null === $output) {
                return;