diff --git a/media/transcoder/README b/media/transcoder/README
index 44de8aa19e..b88313d852 100644
--- a/media/transcoder/README
+++ b/media/transcoder/README
@@ -50,7 +50,17 @@ See the [Transcoder Documentation](https://cloud.google.com/transcoder/docs/) fo
 
 ## Troubleshooting
 
-* See the [Troubleshooting guide](https://cloud.google.com/transcoder/docs/troubleshooting) for more information.
+### bcmath extension missing
+
+If you see an error like this:
+
+```
+PHP Fatal error:  Uncaught Error: Call to undefined function Google\Protobuf\Internal\bcsub()
+```
+
+You need to install the BC-Math extension.
+
+See the [Troubleshooting guide](https://cloud.google.com/transcoder/docs/troubleshooting) for more information.
 
 ## Contributing changes
 
diff --git a/media/transcoder/composer.json b/media/transcoder/composer.json
index 3479371f88..e9713eee86 100644
--- a/media/transcoder/composer.json
+++ b/media/transcoder/composer.json
@@ -1,6 +1,7 @@
 {
     "require": {
         "google/cloud-video-transcoder": "^0.3.0",
-        "google/cloud-storage": "^1.9"
+        "google/cloud-storage": "^1.9",
+        "ext-bcmath":  "*"
     }
 }
diff --git a/media/transcoder/src/create_job_with_concatenated_inputs.php b/media/transcoder/src/create_job_with_concatenated_inputs.php
new file mode 100644
index 0000000000..ad304c4b12
--- /dev/null
+++ b/media/transcoder/src/create_job_with_concatenated_inputs.php
@@ -0,0 +1,125 @@
+<?php
+
+/**
+ * Copyright 2021 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.
+ */
+
+/**
+ * For instructions on how to run the samples:
+ *
+ * @see https://github.com/GoogleCloudPlatform/php-docs-samples/tree/master/media/transcoder/README.md
+ */
+
+namespace Google\Cloud\Samples\Media\Transcoder;
+
+# [START transcoder_create_job_with_concatenated_inputs]
+use Google\Cloud\Video\Transcoder\V1\AudioStream;
+use Google\Cloud\Video\Transcoder\V1\EditAtom;
+use Google\Cloud\Video\Transcoder\V1\ElementaryStream;
+use Google\Cloud\Video\Transcoder\V1\Input;
+use Google\Cloud\Video\Transcoder\V1\Job;
+use Google\Cloud\Video\Transcoder\V1\JobConfig;
+use Google\Cloud\Video\Transcoder\V1\MuxStream;
+use Google\Cloud\Video\Transcoder\V1\TranscoderServiceClient;
+use Google\Cloud\Video\Transcoder\V1\VideoStream;
+use Google\Protobuf\Duration;
+
+/**
+ * Creates a job based on a supplied job config that concatenates two input videos.
+ *
+ * @param string $projectId The ID of your Google Cloud Platform project.
+ * @param string $location The location of the job.
+ * @param string $input1Uri Uri of the first video in the Cloud Storage bucket.
+ * @param float  $startTimeInput1 Start time, in fractional seconds, relative to the first input video timeline.
+ * @param float  $endTimeInput1 End time, in fractional seconds, relative to the first input video timeline.
+ * @param string $input2Uri Uri of the second video in the Cloud Storage bucket.
+ * @param float  $startTimeInput2 Start time, in fractional seconds, relative to the second input video timeline.
+ * @param float  $endTimeInput2 End time, in fractional seconds, relative to the second input video timeline.
+ * @param string $outputUri Uri of the video output folder in the Cloud Storage bucket.
+ */
+function create_job_with_concatenated_inputs($projectId, $location, $input1Uri, $startTimeInput1, $endTimeInput1, $input2Uri, $startTimeInput2, $endTimeInput2, $outputUri)
+{
+    $startTimeInput1Sec = (int) floor(abs($startTimeInput1));
+    $startTimeInput1Nanos = (int) (1000000000 * bcsub(abs($startTimeInput1), floor(abs($startTimeInput1)), 4));
+    $endTimeInput1Sec = (int) floor(abs($endTimeInput1));
+    $endTimeInput1Nanos = (int) (1000000000 * bcsub(abs($endTimeInput1), floor(abs($endTimeInput1)), 4));
+
+    $startTimeInput2Sec = (int) floor(abs($startTimeInput2));
+    $startTimeInput2Nanos = (int) (1000000000 * bcsub(abs($startTimeInput2), floor(abs($startTimeInput2)), 4));
+    $endTimeInput2Sec = (int) floor(abs($endTimeInput2));
+    $endTimeInput2Nanos = (int) (1000000000 * bcsub(abs($endTimeInput2), floor(abs($endTimeInput2)), 4));
+
+    // Instantiate a client.
+    $transcoderServiceClient = new TranscoderServiceClient();
+
+    $formattedParent = $transcoderServiceClient->locationName($projectId, $location);
+    $jobConfig =
+        (new JobConfig())->setInputs([
+            (new Input())
+                ->setKey('input1')
+                ->setUri($input1Uri),
+            (new Input())
+                ->setKey('input2')
+                ->setUri($input2Uri)
+        ])->setEditList([
+            (new EditAtom())
+                ->setKey('atom1')
+                ->setInputs(['input1'])
+                ->setStartTimeOffset(new Duration(['seconds' => $startTimeInput1Sec, 'nanos' => $startTimeInput1Nanos]))
+                ->setEndTimeOffset(new Duration(['seconds' => $endTimeInput1Sec, 'nanos' => $endTimeInput1Nanos])),
+            (new EditAtom())
+                ->setKey('atom2')
+                ->setInputs(['input2'])
+                ->setStartTimeOffset(new Duration(['seconds' => $startTimeInput2Sec, 'nanos' => $startTimeInput2Nanos]))
+                ->setEndTimeOffset(new Duration(['seconds' => $endTimeInput2Sec, 'nanos' => $endTimeInput2Nanos])),
+        ])->setElementaryStreams([
+            (new ElementaryStream())
+                ->setKey('video-stream0')
+                ->setVideoStream(
+                    (new VideoStream())->setH264(
+                        (new VideoStream\H264CodecSettings())
+                            ->setBitrateBps(550000)
+                            ->setFrameRate(60)
+                            ->setHeightPixels(360)
+                            ->setWidthPixels(640)
+                    )
+                ),
+            (new ElementaryStream())
+                ->setKey('audio-stream0')
+                ->setAudioStream(
+                    (new AudioStream())
+                        ->setCodec('aac')
+                        ->setBitrateBps(64000)
+                )
+        ])->setMuxStreams([
+            (new MuxStream())
+                ->setKey('sd')
+                ->setContainer('mp4')
+                ->setElementaryStreams(['video-stream0', 'audio-stream0'])
+        ]);
+
+    $job = (new Job())
+        ->setOutputUri($outputUri)
+        ->setConfig($jobConfig);
+
+    $response = $transcoderServiceClient->createJob($formattedParent, $job);
+
+    // Print job name.
+    printf('Job: %s' . PHP_EOL, $response->getName());
+}
+# [END transcoder_create_job_with_concatenated_inputs]
+
+require_once __DIR__ . '/../../../testing/sample_helpers.php';
+\Google\Cloud\Samples\execute_sample(__FILE__, __NAMESPACE__, $argv);
diff --git a/media/transcoder/test/data/ForBiggerEscapes.mp4 b/media/transcoder/test/data/ForBiggerEscapes.mp4
new file mode 100644
index 0000000000..3ae36b91c8
Binary files /dev/null and b/media/transcoder/test/data/ForBiggerEscapes.mp4 differ
diff --git a/media/transcoder/test/data/ForBiggerJoyrides.mp4 b/media/transcoder/test/data/ForBiggerJoyrides.mp4
new file mode 100644
index 0000000000..33f1dfe1a2
Binary files /dev/null and b/media/transcoder/test/data/ForBiggerJoyrides.mp4 differ
diff --git a/media/transcoder/test/transcoderTest.php b/media/transcoder/test/transcoderTest.php
index b8b9f7d2de..ad460caa9b 100644
--- a/media/transcoder/test/transcoderTest.php
+++ b/media/transcoder/test/transcoderTest.php
@@ -39,8 +39,12 @@ class transcoderTest extends TestCase
 
     private static $testVideoFileName = 'ChromeCast.mp4';
     private static $testOverlayImageFileName = 'overlay.jpg';
+    private static $testConcatVideo1FileName = 'ForBiggerEscapes.mp4';
+    private static $testConcatVideo2FileName = 'ForBiggerJoyrides.mp4';
 
     private static $inputVideoUri;
+    private static $inputConcatVideo1Uri;
+    private static $inputConcatVideo2Uri;
     private static $inputOverlayUri;
     private static $outputUriForPreset;
     private static $outputUriForAdHoc;
@@ -49,6 +53,7 @@ class transcoderTest extends TestCase
     private static $outputUriForStaticOverlay;
     private static $outputUriForPeriodicImagesSpritesheet;
     private static $outputUriForSetNumberImagesSpritesheet;
+    private static $outputUriForConcat;
     private static $preset = 'preset/web-hd';
 
     private static $jobIdRegex;
@@ -71,12 +76,24 @@ public static function setUpBeforeClass(): void
             'name' => self::$testVideoFileName
         ]);
 
+        $file = fopen(__DIR__ . '/data/' . self::$testConcatVideo1FileName, 'r');
+        self::$bucket->upload($file, [
+            'name' => self::$testConcatVideo1FileName
+        ]);
+
+        $file = fopen(__DIR__ . '/data/' . self::$testConcatVideo2FileName, 'r');
+        self::$bucket->upload($file, [
+            'name' => self::$testConcatVideo2FileName
+        ]);
+
         $file = fopen(__DIR__ . '/data/' . self::$testOverlayImageFileName, 'r');
         self::$bucket->upload($file, [
             'name' => self::$testOverlayImageFileName
         ]);
 
         self::$inputVideoUri = sprintf('gs://%s/%s', $bucketName, self::$testVideoFileName);
+        self::$inputConcatVideo1Uri = sprintf('gs://%s/%s', $bucketName, self::$testConcatVideo1FileName);
+        self::$inputConcatVideo2Uri = sprintf('gs://%s/%s', $bucketName, self::$testConcatVideo2FileName);
         self::$inputOverlayUri = sprintf('gs://%s/%s', $bucketName, self::$testOverlayImageFileName);
         self::$outputUriForPreset = sprintf('gs://%s/test-output-preset/', $bucketName);
         self::$outputUriForAdHoc = sprintf('gs://%s/test-output-adhoc/', $bucketName);
@@ -85,6 +102,7 @@ public static function setUpBeforeClass(): void
         self::$outputUriForStaticOverlay = sprintf('gs://%s/test-output-static-overlay/', $bucketName);
         self::$outputUriForPeriodicImagesSpritesheet = sprintf('gs://%s/test-output-periodic-spritesheet/', $bucketName);
         self::$outputUriForSetNumberImagesSpritesheet = sprintf('gs://%s/test-output-set-number-spritesheet/', $bucketName);
+        self::$outputUriForConcat = sprintf('gs://%s/test-output-concat/', $bucketName);
 
         self::$jobIdRegex = sprintf('~projects/%s/locations/%s/jobs/~', self::$projectNumber, self::$location);
     }
@@ -341,4 +359,33 @@ public function testJobSetNumberImagesSpritesheet()
             $jobId
         ]);
     }
+
+    public function testJobConcat()
+    {
+        $output = $this->runFunctionSnippet('create_job_with_concatenated_inputs', [
+            self::$projectId,
+            self::$location,
+            self::$inputConcatVideo1Uri,
+            0,
+            8.1,
+            self::$inputConcatVideo2Uri,
+            3.5,
+            15,
+            self::$outputUriForConcat
+        ]);
+
+        $this->assertRegExp(sprintf('%s', self::$jobIdRegex), $output);
+
+        $jobId = explode('/', $output);
+        $jobId = trim($jobId[(count($jobId) - 1)]);
+
+        sleep(30);
+        $this->assertJobStateSucceeded($jobId);
+
+        $this->runFunctionSnippet('delete_job', [
+            self::$projectId,
+            self::$location,
+            $jobId
+        ]);
+    }
 }