diff --git a/src/Stringy.php b/src/Stringy.php
index 93ad3df..a8bb803 100644
--- a/src/Stringy.php
+++ b/src/Stringy.php
@@ -206,7 +206,7 @@ class Stringy implements \Countable, \IteratorAggregate, \ArrayAccess
 
         $str = mb_strtoupper($first, $this->encoding) . $rest;
 
-        return self::create($str, $this->encoding);
+        return static::create($str, $this->encoding);
     }
 
     /**
@@ -222,7 +222,7 @@ class Stringy implements \Countable, \IteratorAggregate, \ArrayAccess
 
         $str = mb_strtolower($first, $this->encoding) . $rest;
 
-        return self::create($str, $this->encoding);
+        return static::create($str, $this->encoding);
     }
 
     /**
@@ -235,7 +235,7 @@ class Stringy implements \Countable, \IteratorAggregate, \ArrayAccess
     public function camelize()
     {
         $encoding = $this->encoding;
-        $stringy = self::create($this->str, $this->encoding);
+        $stringy = static::create($this->str, $this->encoding);
 
         $camelCase = preg_replace_callback(
             '/[-_\s]+(.)?/u',
@@ -311,7 +311,7 @@ class Stringy implements \Countable, \IteratorAggregate, \ArrayAccess
 
         mb_regex_encoding($regexEncoding);
 
-        return self::create($str, $this->encoding);
+        return static::create($str, $this->encoding);
     }
 
     /**
@@ -321,7 +321,7 @@ class Stringy implements \Countable, \IteratorAggregate, \ArrayAccess
      */
     public function swapCase()
     {
-        $stringy = self::create($this->str, $this->encoding);
+        $stringy = static::create($this->str, $this->encoding);
         $encoding = $stringy->encoding;
 
         $stringy->str = preg_replace_callback(
@@ -378,7 +378,7 @@ class Stringy implements \Countable, \IteratorAggregate, \ArrayAccess
     {
         $str = str_replace(array('_id', '_'), array('', ' '), $this->str);
 
-        return self::create($str, $this->encoding)->trim()->upperCaseFirst();
+        return static::create($str, $this->encoding)->trim()->upperCaseFirst();
     }
 
     /**
@@ -402,7 +402,7 @@ class Stringy implements \Countable, \IteratorAggregate, \ArrayAccess
             '-',
         ), $this->str);
 
-        return self::create($str, $this->encoding);
+        return static::create($str, $this->encoding);
     }
 
     /**
@@ -517,7 +517,7 @@ class Stringy implements \Countable, \IteratorAggregate, \ArrayAccess
 
         $str = preg_replace('/[^\x20-\x7E]/u', '', $str);
 
-        return self::create($str, $this->encoding);
+        return static::create($str, $this->encoding);
     }
 
     /**
@@ -604,7 +604,7 @@ class Stringy implements \Countable, \IteratorAggregate, \ArrayAccess
      */
     private function applyPadding($left = 0, $right = 0, $padStr = ' ')
     {
-        $stringy = self::create($this->str, $this->encoding);
+        $stringy = static::create($this->str, $this->encoding);
         $length = mb_strlen($padStr, $stringy->encoding);
 
         $strLength = $stringy->length();
@@ -684,7 +684,7 @@ class Stringy implements \Countable, \IteratorAggregate, \ArrayAccess
         $spaces = str_repeat(' ', $tabLength);
         $str = str_replace("\t", $spaces, $this->str);
 
-        return self::create($str, $this->encoding);
+        return static::create($str, $this->encoding);
     }
 
     /**
@@ -700,7 +700,7 @@ class Stringy implements \Countable, \IteratorAggregate, \ArrayAccess
         $spaces = str_repeat(' ', $tabLength);
         $str = str_replace($spaces, "\t", $this->str);
 
-        return self::create($str, $this->encoding);
+        return static::create($str, $this->encoding);
     }
 
     /**
@@ -712,7 +712,7 @@ class Stringy implements \Countable, \IteratorAggregate, \ArrayAccess
     {
         $str = mb_convert_case($this->str, MB_CASE_TITLE, $this->encoding);
 
-        return self::create($str, $this->encoding);
+        return static::create($str, $this->encoding);
     }
 
     /**
@@ -725,7 +725,7 @@ class Stringy implements \Countable, \IteratorAggregate, \ArrayAccess
     {
         $str = mb_strtolower($this->str, $this->encoding);
 
-        return self::create($str, $this->encoding);
+        return static::create($str, $this->encoding);
     }
 
     /**
@@ -738,7 +738,7 @@ class Stringy implements \Countable, \IteratorAggregate, \ArrayAccess
     {
         $str = mb_strtoupper($this->str, $this->encoding);
 
-        return self::create($str, $this->encoding);
+        return static::create($str, $this->encoding);
     }
 
     /**
@@ -753,7 +753,7 @@ class Stringy implements \Countable, \IteratorAggregate, \ArrayAccess
      */
     public function slugify($replacement = '-')
     {
-        $stringy = self::create($this->str, $this->encoding);
+        $stringy = static::create($this->str, $this->encoding);
 
         $quotedReplacement = preg_quote($replacement);
         $pattern = "/[^a-zA-Z\d\s-_$quotedReplacement]/u";
@@ -841,7 +841,7 @@ class Stringy implements \Countable, \IteratorAggregate, \ArrayAccess
     {
         $str = implode('', array($substring, $this->str, $substring));
 
-        return self::create($str, $this->encoding);
+        return static::create($str, $this->encoding);
     }
 
     /**
@@ -853,7 +853,7 @@ class Stringy implements \Countable, \IteratorAggregate, \ArrayAccess
      */
     public function insert($substring, $index)
     {
-        $stringy = self::create($this->str, $this->encoding);
+        $stringy = static::create($this->str, $this->encoding);
         if ($index > $stringy->length()) {
             return $stringy;
         }
@@ -878,7 +878,7 @@ class Stringy implements \Countable, \IteratorAggregate, \ArrayAccess
      */
     public function truncate($length, $substring = '')
     {
-        $stringy = self::create($this->str, $this->encoding);
+        $stringy = static::create($this->str, $this->encoding);
         if ($length >= $stringy->length()) {
             return $stringy;
         }
@@ -905,7 +905,7 @@ class Stringy implements \Countable, \IteratorAggregate, \ArrayAccess
      */
     public function safeTruncate($length, $substring = '')
     {
-        $stringy = self::create($this->str, $this->encoding);
+        $stringy = static::create($this->str, $this->encoding);
         if ($length >= $stringy->length()) {
             return $stringy;
         }
@@ -944,7 +944,7 @@ class Stringy implements \Countable, \IteratorAggregate, \ArrayAccess
             $reversed .= mb_substr($this->str, $i, 1, $this->encoding);
         }
 
-        return self::create($reversed, $this->encoding);
+        return static::create($reversed, $this->encoding);
     }
 
     /**
@@ -963,7 +963,7 @@ class Stringy implements \Countable, \IteratorAggregate, \ArrayAccess
             $shuffledStr .= mb_substr($this->str, $i, 1, $this->encoding);
         }
 
-        return self::create($shuffledStr, $this->encoding);
+        return static::create($shuffledStr, $this->encoding);
     }
 
     /**
@@ -973,7 +973,7 @@ class Stringy implements \Countable, \IteratorAggregate, \ArrayAccess
      */
     public function trim()
     {
-        return self::create(trim($this->str), $this->encoding);
+        return static::create(trim($this->str), $this->encoding);
     }
 
     /**
@@ -998,7 +998,7 @@ class Stringy implements \Countable, \IteratorAggregate, \ArrayAccess
             }
         }
 
-        return self::create($longestCommonPrefix, $encoding);
+        return static::create($longestCommonPrefix, $encoding);
     }
 
     /**
@@ -1023,7 +1023,7 @@ class Stringy implements \Countable, \IteratorAggregate, \ArrayAccess
             }
         }
 
-        return self::create($longestCommonSuffix, $encoding);
+        return static::create($longestCommonSuffix, $encoding);
     }
 
     /**
@@ -1038,7 +1038,7 @@ class Stringy implements \Countable, \IteratorAggregate, \ArrayAccess
         // Uses dynamic programming to solve
         // http://en.wikipedia.org/wiki/Longest_common_substring_problem
         $encoding = $this->encoding;
-        $stringy = self::create($this->str, $encoding);
+        $stringy = static::create($this->str, $encoding);
         $strLength = $stringy->length();
         $otherLength = mb_strlen($otherStr, $encoding);
 
@@ -1098,7 +1098,7 @@ class Stringy implements \Countable, \IteratorAggregate, \ArrayAccess
         $length = $length === null ? $this->length() : $length;
         $str = mb_substr($this->str, $start, $length, $this->encoding);
 
-        return self::create($str, $this->encoding);
+        return static::create($str, $this->encoding);
     }
 
     /**
@@ -1120,7 +1120,7 @@ class Stringy implements \Countable, \IteratorAggregate, \ArrayAccess
      */
     public function first($n)
     {
-        $stringy = self::create($this->str, $this->encoding);
+        $stringy = static::create($this->str, $this->encoding);
 
         if ($n < 0) {
             $stringy->str = '';
@@ -1139,7 +1139,7 @@ class Stringy implements \Countable, \IteratorAggregate, \ArrayAccess
      */
     public function last($n)
     {
-        $stringy = self::create($this->str, $this->encoding);
+        $stringy = static::create($this->str, $this->encoding);
 
         if ($n <= 0) {
             $stringy->str = '';
@@ -1159,7 +1159,7 @@ class Stringy implements \Countable, \IteratorAggregate, \ArrayAccess
      */
     public function ensureLeft($substring)
     {
-        $stringy = self::create($this->str, $this->encoding);
+        $stringy = static::create($this->str, $this->encoding);
 
         if (!$stringy->startsWith($substring)) {
             $stringy->str = $substring . $stringy->str;
@@ -1177,7 +1177,7 @@ class Stringy implements \Countable, \IteratorAggregate, \ArrayAccess
      */
     public function ensureRight($substring)
     {
-        $stringy = self::create($this->str, $this->encoding);
+        $stringy = static::create($this->str, $this->encoding);
 
         if (!$stringy->endsWith($substring)) {
             $stringy->str .= $substring;
@@ -1194,7 +1194,7 @@ class Stringy implements \Countable, \IteratorAggregate, \ArrayAccess
      */
     public function removeLeft($substring)
     {
-        $stringy = self::create($this->str, $this->encoding);
+        $stringy = static::create($this->str, $this->encoding);
 
         if ($stringy->startsWith($substring)) {
             $substringLength = mb_strlen($substring, $stringy->encoding);
@@ -1212,7 +1212,7 @@ class Stringy implements \Countable, \IteratorAggregate, \ArrayAccess
      */
     public function removeRight($substring)
     {
-        $stringy = self::create($this->str, $this->encoding);
+        $stringy = static::create($this->str, $this->encoding);
 
         if ($stringy->endsWith($substring)) {
             $substringLength = mb_strlen($substring, $stringy->encoding);
@@ -1379,6 +1379,6 @@ class Stringy implements \Countable, \IteratorAggregate, \ArrayAccess
         $str = mb_ereg_replace($pattern, $replacement, $this->str, $options);
         mb_regex_encoding($regexEncoding);
 
-        return self::create($str, $this->encoding);
+        return static::create($str, $this->encoding);
     }
 }