diff --git a/src/Debugger/DebuggerClient.php b/src/Debugger/DebuggerClient.php
index 6caa12291e08..f6ae8e0922ba 100644
--- a/src/Debugger/DebuggerClient.php
+++ b/src/Debugger/DebuggerClient.php
@@ -141,7 +141,7 @@ public function debuggee($id = null, array $options = [])
      */
     public function debuggees(array $extras = [])
     {
-        $res = $this->connection->listDebuggees(['projectId' => $this->projectId] + $extras);
+        $res = $this->connection->listDebuggees(['project' => $this->projectId] + $extras);
         if (is_array($res) && array_key_exists('debuggees', $res)) {
             return array_map(function ($info) {
                 return new Debuggee($this->connection, $info);
diff --git a/tests/system/Debugger/BasicTest.php b/tests/system/Debugger/BasicTest.php
new file mode 100644
index 000000000000..412dfb59dc73
--- /dev/null
+++ b/tests/system/Debugger/BasicTest.php
@@ -0,0 +1,114 @@
+<?php
+/**
+ * Copyright 2018 Google Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+namespace Google\Cloud\Tests\System\Debugger;
+
+use Google\Cloud\Debugger\Breakpoint;
+use Google\Cloud\Debugger\Debuggee;
+use Google\Cloud\Debugger\DebuggerClient;
+use Google\Cloud\Debugger\V2\Gapic\Debugger2GapicClient as GapicClient;
+use Google\Cloud\Debugger\V2\Breakpoint as GapicBreakpoint;
+use Google\Cloud\Debugger\V2\SourceLocation;
+
+use PHPUnit\Framework\TestCase;
+
+/**
+ * @group debugger
+ */
+class BasicTest extends TestCase
+{
+    private $debuggerClient;
+
+    public function setUp()
+    {
+        $this->debuggerClient = new DebuggerClient([
+            'keyFilePath' => getenv('GOOGLE_CLOUD_PHP_TESTS_KEY_PATH')
+        ]);
+    }
+
+    /**
+     * @dataProvider transports
+     */
+    public function testCanListDebuggees($transport)
+    {
+        $debuggerClient = $this->getClient($transport);
+
+        $debuggees = $debuggerClient->debuggees();
+        $this->assertInternalType('array', $debuggees);
+        $this->assertContainsOnlyInstancesOf(
+            Debuggee::class,
+            $debuggees
+        );
+    }
+
+    /**
+     * @dataProvider transports
+     */
+    public function testRegisterSetUseBreakpoint($transport)
+    {
+        $debuggerClient = $this->getClient($transport);
+
+        $debuggee = $debuggerClient->debuggee('', [
+            'uniquifier' => 'debugger-system-test',
+            'description' => 'Debugger System Test'
+        ]);
+
+        // Register the debuggee
+        $debuggee->register();
+        $this->assertNotEmpty($debuggee->id());
+
+        // Set a breakpoint
+        $client = new GapicClient();
+        $breakpoint = new GapicBreakpoint();
+        $location = new SourceLocation();
+        $location->setPath('web/app.php');
+        $location->setLine(10);
+        $breakpoint->setLocation($location);
+        $resp = $client->setBreakpoint($debuggee->id(), $breakpoint, 'google.com/php/v0.1');
+        $bp = $resp->getBreakpoint();
+        $this->assertNotEmpty($bp->getId());
+
+        // Fetch the list of breakpoints
+        $breakpoints = $debuggee->breakpoints();
+        $this->assertInternalType('array', $breakpoints);
+        $this->assertContainsOnlyInstancesOf(
+            Breakpoint::class,
+            $breakpoints
+        );
+
+        // fulfill a breakpoint
+        $breakpoint = $breakpoints[0];
+        $breakpoint->finalize();
+        $debuggee->updateBreakpoint($breakpoint);
+    }
+
+    public function getClient($transport)
+    {
+        return new DebuggerClient([
+            'transport' => $transport,
+            'keyFilePath' => getenv('GOOGLE_CLOUD_PHP_TESTS_KEY_PATH')
+        ]);
+    }
+
+    public function transports()
+    {
+        return [
+            ['grpc'],
+            ['rest']
+        ];
+    }
+}
diff --git a/tests/unit/Debugger/DebuggerClientTest.php b/tests/unit/Debugger/DebuggerClientTest.php
index 7b67d426da7a..2930e12000c2 100644
--- a/tests/unit/Debugger/DebuggerClientTest.php
+++ b/tests/unit/Debugger/DebuggerClientTest.php
@@ -39,7 +39,7 @@ public function setUp()
 
     public function testListsDebuggees()
     {
-        $this->connection->listDebuggees(['projectId' => 'project1'])->willReturn([
+        $this->connection->listDebuggees(['project' => 'project1'])->willReturn([
             'debuggees' => [
                 ['id' => 'debuggee1', 'project' => 'project1'],
                 ['id' => 'debuggee2', 'project' => 'project1'],
@@ -54,7 +54,7 @@ public function testListsDebuggees()
 
     public function testListsDebuggeesEmpty()
     {
-        $this->connection->listDebuggees(['projectId' => 'project1'])->willReturn([]);
+        $this->connection->listDebuggees(['project' => 'project1'])->willReturn([]);
         $this->client->setConnection($this->connection->reveal());
         $debuggees = $this->client->debuggees();
         $this->assertCount(0, $debuggees);