diff --git a/src/Svg/Document.php b/src/Svg/Document.php
index 0985d28..27c9944 100644
--- a/src/Svg/Document.php
+++ b/src/Svg/Document.php
@@ -23,6 +23,7 @@
 use Svg\Tag\Polyline;
 use Svg\Tag\Rect;
 use Svg\Tag\Stop;
+use Svg\Tag\Symbol;
 use Svg\Tag\Text;
 use Svg\Tag\StyleTag;
 use Svg\Tag\UseTag;
@@ -323,10 +324,14 @@ private function _tagStart($parser, $name, $attributes)
                 break;
 
             case 'g':
-            case 'symbol':
                 $tag = new Group($this, $name);
                 break;
 
+            case 'symbol':
+                $this->inDefs = true;
+                $tag = new Symbol($this, $name);
+                break;
+    
             case 'clippath':
                 $tag = new ClipPath($this, $name);
                 break;
@@ -379,6 +384,11 @@ function _tagEnd($parser, $name)
                 $this->inDefs = false;
                 return;
 
+            case 'symbol':
+                $this->inDefs = false;
+                $tag = array_pop($this->stack);
+                break;
+    
             case 'svg':
             case 'path':
             case 'rect':
@@ -394,7 +404,6 @@ function _tagEnd($parser, $name)
             case 'style':
             case 'text':
             case 'g':
-            case 'symbol':
             case 'clippath':
             case 'use':
             case 'a':
diff --git a/src/Svg/Tag/AbstractTag.php b/src/Svg/Tag/AbstractTag.php
index 708fad0..9d4e0c1 100644
--- a/src/Svg/Tag/AbstractTag.php
+++ b/src/Svg/Tag/AbstractTag.php
@@ -189,6 +189,93 @@ protected function applyTransform($attributes)
         }
     }
 
+    /**
+     * Apply a viewBox transform to the element
+     *
+     * @param array $attributes
+     */
+    protected function applyViewbox($attributes) {
+        if (isset($attributes["viewbox"])) {
+            $surface = $this->document->getSurface();
+            $viewBox = preg_split('/[\s,]+/is', trim($attributes['viewbox']));
+            if (count($viewBox) == 4) {
+                // Computing the equivalent transform of an SVG viewport
+                // https://svgwg.org/svg2-draft/coords.html#ComputingAViewportsTransform
+
+                // 1. Let vb-x, vb-y, vb-width, vb-height be the min-x, min-y, width and height values of the viewBox attribute respectively.
+                [$vbX, $vbY, $vbWidth, $vbHeight] = $viewBox;
+
+                if ($vbWidth < 0 || $vbHeight < 0) {
+                    return;
+                }
+
+                if ($vbWidth == 0 || $vbHeight == 0) {
+                    //TODO: do not render, for now scaling to 0 below
+                }
+
+                // 2. Let e-x, e-y, e-width, e-height be the position and size of the element respectively.
+                $eX = $attributes["x"] ?? 0;
+                $eY = $attributes["y"] ?? 0;
+                $eWidth = $attributes["width"] ?? $this->document->getWidth();
+                $eHeight = $attributes["height"] ?? $this->document->getHeight();
+
+                // 3. Let align be the align value of preserveAspectRatio, or 'xMidYMid' if preserveAspectRatio is not defined.
+                $preserveAspectRatio = explode(" ", $attributes["preserveAspectRatio"] ?? "xMidYMid meet");
+                $align = $preserveAspectRatio[0];
+
+                // 4. Let meetOrSlice be the meetOrSlice value of preserveAspectRatio, or 'meet' if preserveAspectRatio is not defined or if meetOrSlice is missing from this value.
+                $meetOrSlice = $meetOrSlice ?? "meet";
+
+                // 5. Initialize scale-x to e-width/vb-width.
+                $scaleX = $vbWidth == 0 ? 0 : ($eWidth / $vbWidth);
+
+                // 6. Initialize scale-y to e-height/vb-height.
+                $scaleY = $vbHeight == 0 ? 0 : ($eHeight / $vbHeight);
+
+                // 7. If align is not 'none' and meetOrSlice is 'meet', set the larger of scale-x and scale-y to the smaller.
+                if ($align !== "none" && $meetOrSlice === "meet") {
+                    $scaleX = min($scaleX, $scaleY);
+                    $scaleY = min($scaleX, $scaleY);
+                }
+
+                // 8. Otherwise, if align is not 'none' and meetOrSlice is 'slice', set the smaller of scale-x and scale-y to the larger.
+                elseif ($align !== "none" && $meetOrSlice === "slice") {
+                    $scaleX = max($scaleX, $scaleY);
+                    $scaleY = max($scaleX, $scaleY);
+                }
+
+                // 9. Initialize translate-x to e-x - (vb-x * scale-x).
+                $translateX = $eX - ($vbX * $scaleX);
+
+                // 10. Initialize translate-y to e-y - (vb-y * scale-y)
+                $translateY = $eY - ($vbY * $scaleY);
+
+                // 11. If align contains 'xMid', add (e-width - vb-width * scale-x) / 2 to translate-x.
+                if (strpos($align, "xMid") !== false) {
+                    $translateX += ($eWidth - $vbWidth * $scaleX) / 2;
+                }
+
+                // 12. If align contains 'xMax', add (e-width - vb-width * scale-x) to translate-x.
+                if (strpos($align, "xMax") !== false) {
+                    $translateX += ($eWidth - $vbWidth * $scaleX);
+                }
+
+                // 13. If align contains 'yMid', add (e-height - vb-height * scale-y) / 2 to translate-y.
+                if (strpos($align, "yMid") !== false) {
+                    $translateX += ($eHeight - $vbHeight * $scaleY) / 2;
+                }
+
+                // 14. If align contains 'yMax', add (e-height - vb-height * scale-y) to translate-y.
+                if (strpos($align, "yMid") !== false) {
+                    $translateX += ($eHeight - $vbHeight * $scaleY);
+                }
+
+                $surface->translate($translateX, $translateY);
+                $surface->scale($scaleX, $scaleY);
+            }
+        }
+    }
+
     /**
      * Convert the given size for the context of this current tag.
      * Takes a pixel-based reference, which is usually specific to the context of the size,
diff --git a/src/Svg/Tag/Symbol.php b/src/Svg/Tag/Symbol.php
new file mode 100644
index 0000000..d00e7ab
--- /dev/null
+++ b/src/Svg/Tag/Symbol.php
@@ -0,0 +1,34 @@
+<?php
+/**
+ * @package php-svg-lib
+ * @link    http://github.com/PhenX/php-svg-lib
+ * @author  Fabien Ménager <fabien.menager@gmail.com>
+ * @license GNU LGPLv3+ http://www.gnu.org/copyleft/lesser.html
+ */
+
+namespace Svg\Tag;
+
+use Svg\Style;
+
+class Symbol extends AbstractTag
+{
+    protected function before($attributes)
+    {
+        $surface = $this->document->getSurface();
+
+        $surface->save();
+
+        $style = $this->makeStyle($attributes);
+
+        $this->setStyle($style);
+        $surface->setStyle($style);
+
+        $this->applyViewbox($attributes);
+        $this->applyTransform($attributes);
+    }
+
+    protected function after()
+    {
+        $this->document->getSurface()->restore();
+    }
+}
\ No newline at end of file