diff --git a/lib/jasmine-core/jasmine.js b/lib/jasmine-core/jasmine.js
index c95aef3e..25e70185 100644
--- a/lib/jasmine-core/jasmine.js
+++ b/lib/jasmine-core/jasmine.js
@@ -65,6 +65,7 @@ var getJasmineRequireObj = (function(jasmineGlobal) {
     j$.Clock = jRequire.Clock();
     j$.DelayedFunctionScheduler = jRequire.DelayedFunctionScheduler(j$);
     j$.Env = jRequire.Env(j$);
+    j$.deprecatingThisProxy = jRequire.deprecatingThisProxy(j$);
     j$.StackTrace = jRequire.StackTrace(j$);
     j$.ExceptionFormatter = jRequire.ExceptionFormatter(j$);
     j$.ExpectationFilterChain = jRequire.ExpectationFilterChain();
@@ -1956,7 +1957,7 @@ getJasmineRequireObj().Env = function(j$) {
 
       var declarationError = null;
       try {
-        specDefinitions.call(suite);
+        specDefinitions.call(j$.deprecatingThisProxy(suite, self));
       } catch (e) {
         declarationError = e;
       }
@@ -3367,6 +3368,39 @@ getJasmineRequireObj().DelayedFunctionScheduler = function(j$) {
   return DelayedFunctionScheduler;
 };
 
+/* eslint-disable compat/compat */
+// TODO: Remove this in the next major release.
+getJasmineRequireObj().deprecatingThisProxy = function(j$) {
+  var msg = "Access to 'this' in describe functions is deprecated.";
+
+  try {
+    new Proxy({}, {});
+  } catch (e) {
+    // Environment does not support Poxy.
+    return function(suite) {
+      return suite;
+    };
+  }
+
+  function DeprecatingThisProxyHandler(env) {
+    this._env = env;
+  }
+
+  DeprecatingThisProxyHandler.prototype.get = function(target, prop, receiver) {
+    this._env.deprecated(msg);
+    return target[prop];
+  };
+
+  DeprecatingThisProxyHandler.prototype.set = function(target, prop, value) {
+    this._env.deprecated(msg);
+    return (target[prop] = value);
+  };
+
+  return function(suite, env) {
+    return new Proxy(suite, new DeprecatingThisProxyHandler(env));
+  };
+};
+
 getJasmineRequireObj().errors = function() {
   function ExpectationFailed() {}
 
diff --git a/spec/core/EnvSpec.js b/spec/core/EnvSpec.js
index 75979537..12000f34 100644
--- a/spec/core/EnvSpec.js
+++ b/spec/core/EnvSpec.js
@@ -440,4 +440,47 @@ describe('Env', function() {
       done();
     });
   });
+
+  it("deprecates access to 'this' in describes", function() {
+    jasmine.getEnv().requireProxy();
+    var msg = "Access to 'this' in describe functions is deprecated.",
+      ran = false;
+    spyOn(env, 'deprecated');
+
+    env.describe('a suite', function() {
+      expect(this.description).toEqual('a suite');
+      expect(env.deprecated).toHaveBeenCalledWith(msg);
+      env.deprecated.calls.reset();
+
+      this.foo = 1;
+      expect(env.deprecated).toHaveBeenCalledWith(msg);
+      expect(this.foo).toEqual(1);
+      env.deprecated.calls.reset();
+
+      expect(this.getFullName()).toEqual('a suite');
+      expect(env.deprecated).toHaveBeenCalledWith(msg);
+      env.deprecated.calls.reset();
+
+      env.it('has a spec');
+      ran = true;
+    });
+
+    expect(ran).toBeTrue();
+  });
+
+  // TODO: Remove this in the next major version. Suites were never meant to be
+  // exposed via describe 'this' in >= 2.0, and user code should not rely on it.
+  // This spec is just here to make sure we don't break user code that *does*
+  // rely on it in older browsers (without Proxy) while deprecating it.
+  it("sets 'this' to the Suite in describes", function() {
+    var suiteThis;
+    spyOn(env, 'deprecated');
+
+    env.describe('a suite', function() {
+      suiteThis = this;
+      env.it('has a spec');
+    });
+
+    expect(suiteThis).toBeInstanceOf(jasmineUnderTest.Suite);
+  });
 });
diff --git a/spec/helpers/checkForProxy.js b/spec/helpers/checkForProxy.js
new file mode 100644
index 00000000..b4062d0b
--- /dev/null
+++ b/spec/helpers/checkForProxy.js
@@ -0,0 +1,17 @@
+/* eslint-disable compat/compat */
+(function(env) {
+  function hasProxyConstructor() {
+    try {
+      new Proxy({}, {});
+      return true;
+    } catch (e) {
+      return false;
+    }
+  }
+
+  env.requireProxy = function() {
+    if (!hasProxyConstructor()) {
+      env.pending('Environment does not support Proxy');
+    }
+  };
+})(jasmine.getEnv());
diff --git a/spec/support/jasmine-browser.js b/spec/support/jasmine-browser.js
index 9062bf8a..1fc16d01 100644
--- a/spec/support/jasmine-browser.js
+++ b/spec/support/jasmine-browser.js
@@ -21,6 +21,7 @@ module.exports = {
     'helpers/generator.js',
     'helpers/BrowserFlags.js',
     'helpers/checkForMap.js',
+    'helpers/checkForProxy.js',
     'helpers/checkForSet.js',
     'helpers/checkForSymbol.js',
     'helpers/checkForUrl.js',
diff --git a/spec/support/jasmine.json b/spec/support/jasmine.json
index 1a0ca3b2..d6369bf2 100644
--- a/spec/support/jasmine.json
+++ b/spec/support/jasmine.json
@@ -8,6 +8,7 @@
     "helpers/asyncAwait.js",
     "helpers/generator.js",
     "helpers/checkForMap.js",
+    "helpers/checkForProxy.js",
     "helpers/checkForSet.js",
     "helpers/checkForSymbol.js",
     "helpers/checkForUrl.js",
diff --git a/src/core/Env.js b/src/core/Env.js
index 138711e0..813c4843 100644
--- a/src/core/Env.js
+++ b/src/core/Env.js
@@ -987,7 +987,7 @@ getJasmineRequireObj().Env = function(j$) {
 
       var declarationError = null;
       try {
-        specDefinitions.call(suite);
+        specDefinitions.call(j$.deprecatingThisProxy(suite, self));
       } catch (e) {
         declarationError = e;
       }
diff --git a/src/core/deprecatingThisProxy.js b/src/core/deprecatingThisProxy.js
new file mode 100644
index 00000000..6f924b18
--- /dev/null
+++ b/src/core/deprecatingThisProxy.js
@@ -0,0 +1,32 @@
+/* eslint-disable compat/compat */
+// TODO: Remove this in the next major release.
+getJasmineRequireObj().deprecatingThisProxy = function(j$) {
+  var msg = "Access to 'this' in describe functions is deprecated.";
+
+  try {
+    new Proxy({}, {});
+  } catch (e) {
+    // Environment does not support Poxy.
+    return function(suite) {
+      return suite;
+    };
+  }
+
+  function DeprecatingThisProxyHandler(env) {
+    this._env = env;
+  }
+
+  DeprecatingThisProxyHandler.prototype.get = function(target, prop, receiver) {
+    this._env.deprecated(msg);
+    return target[prop];
+  };
+
+  DeprecatingThisProxyHandler.prototype.set = function(target, prop, value) {
+    this._env.deprecated(msg);
+    return (target[prop] = value);
+  };
+
+  return function(suite, env) {
+    return new Proxy(suite, new DeprecatingThisProxyHandler(env));
+  };
+};
diff --git a/src/core/requireCore.js b/src/core/requireCore.js
index aac94b87..13cc6cc5 100644
--- a/src/core/requireCore.js
+++ b/src/core/requireCore.js
@@ -43,6 +43,7 @@ var getJasmineRequireObj = (function(jasmineGlobal) {
     j$.Clock = jRequire.Clock();
     j$.DelayedFunctionScheduler = jRequire.DelayedFunctionScheduler(j$);
     j$.Env = jRequire.Env(j$);
+    j$.deprecatingThisProxy = jRequire.deprecatingThisProxy(j$);
     j$.StackTrace = jRequire.StackTrace(j$);
     j$.ExceptionFormatter = jRequire.ExceptionFormatter(j$);
     j$.ExpectationFilterChain = jRequire.ExpectationFilterChain();