diff --git a/README.md b/README.md
index b9becff5..132183c4 100644
--- a/README.md
+++ b/README.md
@@ -45,7 +45,6 @@ Table of Contents
      * [some()](#some)
      * [map()](#map)
      * [reduce()](#reduce)
-   * [PromisorInterface](#promisorinterface)
 4. [Examples](#examples)
    * [How to use Deferred](#how-to-use-deferred)
    * [How promise forwarding works](#how-promise-forwarding-works)
@@ -486,12 +485,6 @@ promises and/or values, and `$reduceFunc` may return either a value or a
 promise, *and* `$initialValue` may be a promise or a value for the starting
 value.
 
-### PromisorInterface
-
-The `React\Promise\PromisorInterface` provides a common interface for objects
-that provide a promise. `React\Promise\Deferred` implements it, but since it
-is part of the public API anyone can implement it.
-
 Examples
 --------
 
diff --git a/src/Deferred.php b/src/Deferred.php
index ee4fdfa9..b1abfd3c 100644
--- a/src/Deferred.php
+++ b/src/Deferred.php
@@ -2,7 +2,7 @@
 
 namespace React\Promise;
 
-final class Deferred implements PromisorInterface
+final class Deferred
 {
     private $promise;
     private $resolveCallback;
diff --git a/src/PromisorInterface.php b/src/PromisorInterface.php
deleted file mode 100644
index 87e999c1..00000000
--- a/src/PromisorInterface.php
+++ /dev/null
@@ -1,13 +0,0 @@
-<?php
-
-namespace React\Promise;
-
-interface PromisorInterface
-{
-    /**
-     * Returns the promise of the deferred.
-     *
-     * @return PromiseInterface
-     */
-    public function promise(): PromiseInterface;
-}