diff --git a/composer.json b/composer.json
index 812d691..37041ca 100644
--- a/composer.json
+++ b/composer.json
@@ -15,7 +15,8 @@
 
     "minimum-stability": "stable",
     "require":           {
-        "php": "^8.1"
+        "php":            "^8.1",
+        "sgh/comparable": "^1.1"
     },
     "autoload":          {
         "psr-4":                 {
@@ -40,4 +41,4 @@
         "docs":   "https://git.jrosset.ovh/jrosset/PhpCollections/wiki",
         "source": "https://git.jrosset.ovh/jrosset/PhpCollections"
     }
-}
\ No newline at end of file
+}
diff --git a/src/Collections/IImmutableCollection.php b/src/Collections/IImmutableCollection.php
index 6bc3bc6..a69571c 100644
--- a/src/Collections/IImmutableCollection.php
+++ b/src/Collections/IImmutableCollection.php
@@ -7,6 +7,9 @@ use Closure;
 use Countable;
 use IteratorAggregate;
 use JsonSerializable;
+use SGH\Comparable\Comparable;
+use SGH\Comparable\Comparator;
+use Throwable;
 
 /**
  * Interface for an immutable (read-only) collection
@@ -125,6 +128,34 @@ interface IImmutableCollection extends IteratorAggregate, JsonSerializable, Coun
      */
     public function map (Closure $process): self;
 
+    /**
+     * Sort the elements (by value)
+     *
+     * @param null|Comparator|Closure(TValue, TValue):int $sorter The sorting method ; Null if values are object implementing {@see Comparable}.
+     *                                                            <br>Return :
+     *                                                            <br>&lt; 0 if value1 is before value2
+     *                                                            <br>= 0 if value1 equals value2
+     *                                                            <br>&gt; 0 if value1 is after value2
+     *
+     * @return self The sorted collection
+     *
+     * @throws Throwable If an error occurs
+     */
+    public function sort (Closure|Comparator|null $sorter = null): self;
+    /**
+     * Sort the elements by key
+     *
+     * @param Comparator|Closure(TKey, TKey):int $sorter The sorting method. Return :
+     *                                                   <br>&lt; 0 if key1 is before key2
+     *                                                   <br>= 0 if key1 equals key2
+     *                                                   <br>&gt; 0 if key1 is after key2
+     *
+     * @return self The sorted collection
+     *
+     * @throws Throwable If an error occurs
+     */
+    public function sortByKey (Closure|Comparator $sorter): self;
+
     /**
      * The list of all keys
      *
@@ -163,7 +194,7 @@ interface IImmutableCollection extends IteratorAggregate, JsonSerializable, Coun
      *
      * @param IImmutableCollection ...$collections The other collections to combine
      *
-     * @return static The combine collection
+     * @return static The combined collection
      */
     public function combineWith (IImmutableCollection ...$collections): self;
 }
\ No newline at end of file
diff --git a/src/Collections/ImmutableCollection.php b/src/Collections/ImmutableCollection.php
index f5f02e8..c89b247 100644
--- a/src/Collections/ImmutableCollection.php
+++ b/src/Collections/ImmutableCollection.php
@@ -5,6 +5,8 @@ namespace jrosset\Collections;
 use ArrayIterator;
 use Closure;
 use InvalidArgumentException;
+use SGH\Comparable\Comparable;
+use SGH\Comparable\Comparator;
 use Traversable;
 
 /**
@@ -46,7 +48,7 @@ class ImmutableCollection implements IImmutableCollection {
      * @throws InvalidArgumentException If the initial values aren't valid
      * @internal
      */
-    protected function _initialize (?iterable $other = null) {
+    protected function _initialize (?iterable $other = null): void {
         $this->elements = [];
         if ($other !== null) {
             if (!is_array($other) && !$other instanceof Traversable) {
@@ -300,6 +302,42 @@ class ImmutableCollection implements IImmutableCollection {
         return $output;
     }
 
+    /**
+     * @inheritDoc
+     */
+    public function sort (Closure|Comparator|null $sorter = null): static {
+        if ($sorter === null) {
+            $sorter = function (Comparable $value1, Comparable $value2): int {
+                return $value1->compareTo($value2);
+            };
+        }
+        elseif ($sorter instanceof Comparator) {
+            $sorter = function ($value1, $value2) use ($sorter): int {
+                return $sorter->compare($value1, $value2);
+            };
+        }
+
+        $elements = $this->toArray();
+        uasort($elements, $sorter);
+
+        return new static($elements);
+    }
+    /**
+     * @inheritDoc
+     */
+    public function sortByKey (Closure|Comparator $sorter): static {
+        if ($sorter instanceof Comparator) {
+            $sorter = function ($value1, $value2) use ($sorter): int {
+                return $sorter->compare($value1, $value2);
+            };
+        }
+
+        $elements = $this->toArray();
+        uksort($elements, $sorter);
+
+        return new static($elements);
+    }
+
     /**
      * @inheritDoc
      */