diff --git a/src/Prometheus/CollectorRegistry.php b/src/Prometheus/CollectorRegistry.php
index 9ff18e3..fc604b4 100644
--- a/src/Prometheus/CollectorRegistry.php
+++ b/src/Prometheus/CollectorRegistry.php
@@ -49,6 +49,14 @@ public static function getDefault()
         return self::$defaultRegistry;
     }
 
+    /**
+     * @return boolean
+     */
+    public function initialized()
+    {
+        return $this->storageAdapter->initialized();
+    }
+
     /**
      * @return MetricFamilySamples[]
      */
diff --git a/src/Prometheus/Storage/APC.php b/src/Prometheus/Storage/APC.php
index b5a9c4b..c317f87 100644
--- a/src/Prometheus/Storage/APC.php
+++ b/src/Prometheus/Storage/APC.php
@@ -10,6 +10,14 @@ class APC implements Adapter
 {
     const PROMETHEUS_PREFIX = 'prom';
 
+    /**
+     * @return boolean
+     */
+    public function initialized()
+    {
+        return !apc_add(self::PROMETHEUS_PREFIX . ":initialized", true);
+    }
+
     /**
      * @return MetricFamilySamples[]
      */
diff --git a/src/Prometheus/Storage/Adapter.php b/src/Prometheus/Storage/Adapter.php
index e280f13..03818a5 100644
--- a/src/Prometheus/Storage/Adapter.php
+++ b/src/Prometheus/Storage/Adapter.php
@@ -11,6 +11,11 @@ interface Adapter
     const COMMAND_INCREMENT_FLOAT = 2;
     const COMMAND_SET = 3;
 
+    /**
+     * @return boolean
+     */
+    public function initialized();
+
     /**
      * @return MetricFamilySamples[]
      */
diff --git a/src/Prometheus/Storage/InMemory.php b/src/Prometheus/Storage/InMemory.php
index 37c24b1..7972381 100644
--- a/src/Prometheus/Storage/InMemory.php
+++ b/src/Prometheus/Storage/InMemory.php
@@ -11,6 +11,19 @@ class InMemory implements Adapter
     private $counters = [];
     private $gauges = [];
     private $histograms = [];
+    private $initialized = false;
+
+    /**
+     * @return boolean
+     */
+    public function initialized()
+    {
+        if(!$this->initialized){
+            $this->initialized = true;
+            return false;
+        }
+        return $this->initialized;
+    }
 
     /**
      * @return MetricFamilySamples[]
@@ -28,6 +41,7 @@ public function flushMemory()
         $this->counters = [];
         $this->gauges = [];
         $this->histograms = [];
+        $this->initialized = false;
     }
 
     private function collectHistograms()
diff --git a/src/Prometheus/Storage/Redis.php b/src/Prometheus/Storage/Redis.php
index f38391b..459d08d 100644
--- a/src/Prometheus/Storage/Redis.php
+++ b/src/Prometheus/Storage/Redis.php
@@ -19,6 +19,11 @@ class Redis implements Adapter
     private $options;
     private $redis;
 
+    public function initialized()
+    {
+        return $this->redis->getSet(self::$prefix . 'INITIALIZED', 1);
+    }
+
     public function __construct(array $options = array())
     {
         // with php 5.3 we cannot initialize the options directly on the field definition