diff --git a/.github/workflows/tests.yml b/.github/workflows/tests.yml
index f2f0758..191951b 100644
--- a/.github/workflows/tests.yml
+++ b/.github/workflows/tests.yml
@@ -9,7 +9,7 @@ jobs:
         strategy:
             fail-fast: true
             matrix:
-                php: [7.3, 7.4]
+                php: [7.4]
                 laravel: [8.*]
                 dependency-version: [prefer-lowest, prefer-stable]
 
@@ -17,13 +17,16 @@ jobs:
 
         steps:
             -   name: Checkout the code
-                uses: actions/checkout@v1
+                uses: actions/checkout@v2
 
-            -   name: Disable Xdebug
-                run: sudo phpdismod xdebug
+            -   name: Setup PHP
+                uses: shivammathur/setup-php@v2
+                with:
+                    php-version: ${{ matrix.php }}
+                    extensions: simplexml
 
             -   name: Install dependencies
-                run: composer install --no-progress --no-ansi --profile --no-interaction --no-scripts --no-suggest --prefer-dist
+                run: composer install --no-progress --no-ansi --profile --no-interaction --no-scripts --prefer-dist
 
             -   name: Execute tests
                 run: vendor/bin/phpunit --testdox --colors=always --exclude-group skipped
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 11c3a52..fe7e780 100755
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -4,6 +4,10 @@ All notable changes to `netgsm` will be documented in this file
 
 ## Unreleased
 
+## [4.0.0] - 2021-04-26
+
+- IYS integration (add, search) added.
+
 ## [3.0.1] - 2020-10-08
 
 - Upgrade packages for Laravel 8.
diff --git a/README.md b/README.md
index 6a954b9..3e5ba06 100755
--- a/README.md
+++ b/README.md
@@ -25,6 +25,9 @@ This package also provides some simple reporting.
    - [Account Balance](#account-balance)
         - [Remaining Balance](#remaining-balance)
         - [Remaining Package Credits](#remaining-package-credits)
+   - [IYS Integration](#iys-integration)
+        - [Add Address](#add-address)
+        - [Search Address](#search-address)
 - [Testing](#testing)
 - [Security](#security)
 - [Contributing](#contributing)
@@ -56,6 +59,7 @@ NETGSM_USER_CODE=
 NETGSM_SECRET=
 NETGSM_LANGUAGE=
 NETGSM_HEADER=
+NETGSM_BRANDCODE=
 ],
 ...
 ```
@@ -298,6 +302,105 @@ class Illuminate\Support\Collection#105 (1) {
 }
 ```
 
+### IYS Integration
+
+With these services you can add and search any address to IYS.
+
+#### Add Address
+
+This service is used to add a phone number or email address to IYS using NetGsm IYS service.
+
+##### Object Parameters
+
+| Method                | Description | Type | Required | 
+| --------------------- | ----------- | ---- | -------- |
+| setRefId()            | Reference id to query your request | String | No
+| setType()             | Communication type | String | Yes
+| setSource()           | Source of permission | String | Yes
+| setRecipient()        | phone number or email address | String | Yes
+| setStatus()           | Permission status | String | Yes
+| setConsentDate()      | Permission date | Datetime (YYYY-MM-DD H:i:s) | Yes
+| setRecipientType()    | Recipient type | String | Yes
+| setRetailerCode()     | Retailer code | Integer | No
+| setRetailerAccess()   | Retailer access | Integer | No
+
+##### Usage
+
+```php
+$address = new \TarfinLabs\Netgsm\Iys\Requests\Add();
+$address->setRefId(999999)
+        ->setType('MESAJ')
+        ->setSource('HS_WEB')
+        ->setRecipient('+905XXXXXXXXX')
+        ->setStatus('ONAY')
+        ->setConsentDate(now()->toDateTimeString())
+        ->setRecipientType('TACIR');
+
+\TarfinLabs\Netgsm\Netgsm::iys()->addAddress($address)->send();
+```
+
+##### Response Parameters
+```json
+{
+    "code": "0",
+    "error": "false",
+    "uid": "73113cb9-dff0-415b-9491-xxxxxxxxxx"
+}
+```
+
+#### Search Address
+
+This service is used to search a phone number or email address on IYS using NetGsm IYS service.
+
+##### Object Parameters
+
+| Method                | Description | Type | Required | 
+| --------------------- | ----------- | ---- | -------- |
+| setType()             | Communication type | String | Yes (if refId is set to null)
+| setRecipient()        | phone number or email address | String | Yes (if refId is set to null)
+| setRecipientType()    | Recipient type | String | Yes (if refId is set to null)
+| setRefId()            | Reference id to query your request | String | No
+
+##### Usage
+
+```php
+$address = new \TarfinLabs\Netgsm\Iys\Requests\Search();
+$address->setType('MESAJ')
+        ->setRecipient('+905XXXXXXXXX')
+        ->setRecipientType('TACIR')
+        ->setRefId(999999);
+
+\TarfinLabs\Netgsm\Netgsm::iys()->searchAddress($address)->send();
+```
+
+##### Response Parameters
+* Response with a matched address.
+```json
+{
+    "code": "0",
+    "error": "false",
+    "query": {
+        "consentDate": "2020-11-06 11:22:34",
+        "source": "HS_FIZIKSEL_ORTAM",
+        "recipient": "+905XXXXXXXXX",
+        "recipientType": "BIREYSEL",
+        "type": "MESAJ",
+        "status": "ONAY",
+        "creationDate": "2020-11-06 11:23:49",
+        "retailerAccessCount": 0
+        // "querystatus": null
+    }
+}
+```
+
+* Response without any matched address
+```json
+{
+    "code": "50",
+    "error": "Kayıt bulunamadi."
+}
+```
+
 ### Testing
 
 ``` bash
diff --git a/composer.json b/composer.json
index 7a3847a..1c9193d 100755
--- a/composer.json
+++ b/composer.json
@@ -31,7 +31,7 @@
         }
     ],
     "require": {
-        "php": "^7.3",
+        "php": "^7.4",
         "guzzlehttp/guzzle": "^7.1",
         "illuminate/support": "^8.0",
         "illuminate/notifications": "^8.0",
@@ -40,7 +40,7 @@
         "ext-simplexml": "*"
     },
     "require-dev": {
-        "fzaninotto/faker": "^1.9",
+        "fakerphp/faker": "^1.14",
         "phpunit/phpunit": "^9.4",
         "mockery/mockery": "^1.4",
         "orchestra/testbench": "^6.0"
diff --git a/config/config.php b/config/config.php
index 48f29e9..9eed397 100755
--- a/config/config.php
+++ b/config/config.php
@@ -4,6 +4,7 @@
     'credentials' => [
         'user_code' => env('NETGSM_USERCODE'),
         'secret'    => env('NETGSM_SECRET'),
+        'brand_code'=> env('NETGSM_BRANDCODE'),
     ],
     'defaults'    => [
         'language'           => env('NETGSM_LANGUAGE', 'tr'),
diff --git a/src/Iys/AbstractNetgsmIys.php b/src/Iys/AbstractNetgsmIys.php
new file mode 100644
index 0000000..c7c7533
--- /dev/null
+++ b/src/Iys/AbstractNetgsmIys.php
@@ -0,0 +1,42 @@
+<?php
+
+namespace TarfinLabs\Netgsm\Iys;
+
+use TarfinLabs\Netgsm\NetgsmApiClient;
+
+abstract class AbstractNetgsmIys extends NetgsmApiClient
+{
+    protected string $url = '';
+
+    protected string $method = 'GET';
+
+    protected array $body = [];
+
+    /**
+     * Send request.
+     *
+     * @return string
+     */
+    public function send(): string
+    {
+        $response = $this->client->request($this->method, $this->url, [
+            'headers'       => [
+                'Content-Type'  => 'application/json',
+            ],
+            'json' => [
+                'header'    => [
+                    'username'  => $this->credentials['user_code'],
+                    'password'  => $this->credentials['secret'],
+                    'brandCode' => $this->credentials['brand_code'],
+                ],
+                'body'      => [
+                    'data'      => [
+                        $this->body,
+                    ],
+                ],
+            ],
+        ]);
+
+        return $response->getBody()->getContents();
+    }
+}
diff --git a/src/Iys/NetgsmIys.php b/src/Iys/NetgsmIys.php
new file mode 100644
index 0000000..a8dde89
--- /dev/null
+++ b/src/Iys/NetgsmIys.php
@@ -0,0 +1,39 @@
+<?php
+
+namespace TarfinLabs\Netgsm\Iys;
+
+use TarfinLabs\Netgsm\Iys\Requests\Add;
+use TarfinLabs\Netgsm\Iys\Requests\Search;
+
+class NetgsmIys extends AbstractNetgsmIys
+{
+    /**
+     * Add address request.
+     *
+     * @param Add $request
+     * @return $this
+     */
+    public function addAddress(Add $request): NetgsmIys
+    {
+        $this->url = $request->getUrl();
+        $this->body = $request->body();
+        $this->method = 'POST';
+
+        return $this;
+    }
+
+    /**
+     * Search address request.
+     *
+     * @param Search $request
+     * @return $this
+     */
+    public function searchAddress(Search $request): NetgsmIys
+    {
+        $this->url = $request->getUrl();
+        $this->body = $request->body();
+        $this->method = 'POST';
+
+        return $this;
+    }
+}
diff --git a/src/Iys/Requests/Add.php b/src/Iys/Requests/Add.php
new file mode 100644
index 0000000..b64b7aa
--- /dev/null
+++ b/src/Iys/Requests/Add.php
@@ -0,0 +1,170 @@
+<?php
+
+namespace TarfinLabs\Netgsm\Iys\Requests;
+
+class Add
+{
+    protected string $url = 'iys/add';
+
+    protected string $refId;
+
+    protected string $type;
+
+    protected string $source;
+
+    protected string $recipient;
+
+    protected string $status;
+
+    protected string $consentDate;
+
+    protected string $recipientType;
+
+    protected ?int $retailerCode;
+
+    protected ?int $retailerAccess;
+
+    /**
+     * @param string $refId
+     * @return $this
+     */
+    public function setRefId(string $refId): self
+    {
+        $this->refId = $refId;
+
+        return $this;
+    }
+
+    /**
+     * @param string $type
+     * @return $this
+     */
+    public function setType(string $type): self
+    {
+        $this->type = $type;
+
+        return $this;
+    }
+
+    /**
+     * @param string $source
+     * @return $this
+     */
+    public function setSource(string $source): self
+    {
+        $this->source = $source;
+
+        return $this;
+    }
+
+    /**
+     * @param string $recipient
+     * @return $this
+     */
+    public function setRecipient(string $recipient): self
+    {
+        $this->recipient = $recipient;
+
+        return $this;
+    }
+
+    /**
+     * @param string $status
+     * @return $this
+     */
+    public function setStatus(string $status): self
+    {
+        $this->status = $status;
+
+        return $this;
+    }
+
+    /**
+     * @param string $consentDate
+     * @return $this
+     */
+    public function setConsentDate(string $consentDate): self
+    {
+        $this->consentDate = $consentDate;
+
+        return $this;
+    }
+
+    /**
+     * @param string $recipientType
+     * @return $this
+     */
+    public function setRecipientType(string $recipientType): self
+    {
+        $this->recipientType = $recipientType;
+
+        return $this;
+    }
+
+    /**
+     * @param int|null $retailerCode
+     * @return $this
+     */
+    public function setRetailerCode(?int $retailerCode): self
+    {
+        $this->retailerCode = $retailerCode;
+
+        return $this;
+    }
+
+    /**
+     * @param int|null $retailerAccess
+     * @return $this
+     */
+    public function setRetailerAccess(?int $retailerAccess): self
+    {
+        $this->retailerAccess = $retailerAccess;
+
+        return $this;
+    }
+
+    /**
+     * @param array $defaults
+     * @return $this
+     */
+    public function setDefaults(array $defaults): self
+    {
+        foreach ($defaults as $key => $value) {
+            if (method_exists($this, 'set'.ucfirst($key))) {
+                call_user_func([$this, 'set'.ucfirst($key)], $value);
+            }
+        }
+
+        return $this;
+    }
+
+    /**
+     * Get request body.
+     *
+     * @return array
+     */
+    public function body(): array
+    {
+        return [
+            'refid'             => $this->refId ?? null,
+            'type'              => $this->type ?? null,
+            'source'            => $this->source ?? null,
+            'recipient'         => $this->recipient ?? null,
+            'status'            => $this->status ?? null,
+            'consentDate'       => $this->consentDate ?? null,
+            'recipientType'     => $this->recipientType ?? null,
+            'retailerCode'      => $this->retailerCode ?? null,
+            'retailerAccess'    => $this->retailerAccess ?? null,
+        ];
+    }
+
+    /**
+     * Get request url.
+     *
+     * @return string
+     */
+    public function getUrl(): string
+    {
+        return $this->url;
+    }
+}
diff --git a/src/Iys/Requests/Search.php b/src/Iys/Requests/Search.php
new file mode 100644
index 0000000..0b16d89
--- /dev/null
+++ b/src/Iys/Requests/Search.php
@@ -0,0 +1,100 @@
+<?php
+
+namespace TarfinLabs\Netgsm\Iys\Requests;
+
+class Search
+{
+    protected string $url = 'iys/search';
+
+    protected string $type;
+
+    protected string $recipient;
+
+    protected string $recipientType;
+
+    protected string $refId;
+
+    /**
+     * @param string $type
+     * @return $this
+     */
+    public function setType(string $type): self
+    {
+        $this->type = $type;
+
+        return $this;
+    }
+
+    /**
+     * @param string $recipient
+     * @return $this
+     */
+    public function setRecipient(string $recipient): self
+    {
+        $this->recipient = $recipient;
+
+        return $this;
+    }
+
+    /**
+     * @param string $recipientType
+     * @return $this
+     */
+    public function setRecipientType(string $recipientType): self
+    {
+        $this->recipientType = $recipientType;
+
+        return $this;
+    }
+
+    /**
+     * @param string $refId
+     * @return $this
+     */
+    public function setRefId(string $refId): self
+    {
+        $this->refId = $refId;
+
+        return $this;
+    }
+
+    /**
+     * @param array $defaults
+     * @return $this
+     */
+    public function setDefaults(array $defaults): self
+    {
+        foreach ($defaults as $key => $value) {
+            if (method_exists($this, 'set'.ucfirst($key))) {
+                call_user_func([$this, 'set'.ucfirst($key)], $value);
+            }
+        }
+
+        return $this;
+    }
+
+    /**
+     * Get request body.
+     *
+     * @return array
+     */
+    public function body(): array
+    {
+        return [
+            'type'              => $this->type ?? null,
+            'recipient'         => $this->recipient ?? null,
+            'recipientType'     => $this->recipientType ?? null,
+            'refid'             => $this->refId ?? null,
+        ];
+    }
+
+    /**
+     * Get request url.
+     *
+     * @return string
+     */
+    public function getUrl(): string
+    {
+        return $this->url;
+    }
+}
diff --git a/src/Netgsm.php b/src/Netgsm.php
index c9104a4..c6d6cee 100644
--- a/src/Netgsm.php
+++ b/src/Netgsm.php
@@ -9,6 +9,7 @@
 use TarfinLabs\Netgsm\Balance\NetgsmAvailableCredit;
 use TarfinLabs\Netgsm\Balance\NetgsmPackages;
 use TarfinLabs\Netgsm\Exceptions\CouldNotSendNotification;
+use TarfinLabs\Netgsm\Iys\NetgsmIys;
 use TarfinLabs\Netgsm\Report\AbstractNetgsmReport;
 use TarfinLabs\Netgsm\Sms\AbstractNetgsmMessage;
 
@@ -126,4 +127,15 @@ public function getAvailablePackages(): Collection
 
         return collect($packageService->getPackages());
     }
+
+    /**
+     * @return NetgsmIys
+     */
+    public function iys(): NetgsmIys
+    {
+        $iysService = new NetgsmIys();
+        $iysService->setClient($this->client)->setCredentials($this->credentials);
+
+        return $iysService;
+    }
 }
diff --git a/tests/NetGsmIysTest.php b/tests/NetGsmIysTest.php
new file mode 100644
index 0000000..35ad786
--- /dev/null
+++ b/tests/NetGsmIysTest.php
@@ -0,0 +1,129 @@
+<?php
+
+namespace TarfinLabs\Netgsm\Tests;
+
+use GuzzleHttp\Client;
+use GuzzleHttp\Psr7\Response;
+use Mockery;
+use Psr\Http\Message\ResponseInterface;
+use TarfinLabs\Netgsm\Iys\Requests\Add;
+use TarfinLabs\Netgsm\Iys\Requests\Search;
+use TarfinLabs\Netgsm\Netgsm;
+
+class NetGsmIysTest extends BaseTestCase
+{
+    protected Netgsm $netgsm;
+
+    protected Client $httpClient;
+
+    protected ResponseInterface $response;
+
+    public function setUp(): void
+    {
+        parent::setUp();
+
+        $this->httpClient = Mockery::mock(new Client());
+        $this->response = Mockery::mock(ResponseInterface::class);
+
+        $this->netgsm = new Netgsm($this->httpClient, [
+            'user_code'  => 'test',
+            'secret'     => 'test',
+            'brand_code' => 123456,
+        ]);
+    }
+
+    /** @test */
+    public function it_makes_add_requests_for_iys_addresses()
+    {
+        $data = [
+            'headers' => [
+                'Content-Type'      => 'application/json',
+            ],
+            'json'    => [
+                'header' => [
+                    'username'      => 'test',
+                    'password'      => 'test',
+                    'brandCode'     => 123456,
+                ],
+                'body'   => [
+                    'data' => [
+                        [
+                            'refid'         => $this->faker->numerify('####'),
+                            'type'          => $this->faker->randomElement(['MESAJ', 'ARAMA']),
+                            'source'        => $this->faker->randomElement([
+                                'HS_WEB',
+                                'HS_FIZIKSEL_ORTAM',
+                                'HS_ISLAK_IMZA',
+                                'HS_CAGRI_MERKEZI',
+                                'HS_SOSYAL_MEDYA',
+                                'HS_EPOSTA',
+                                'HS_MESAJ',
+                                'HS_MOBIL',
+                                'HS_EORTAM',
+                                'HS_ETKINLIK',
+                                'HS_2015',
+                                'HS_ATM',
+                                'HS_KARAR',
+                            ]),
+                            'recipient'     => $this->faker->numerify('+905#########'),
+                            'status'        => $this->faker->randomElement(['ONAY', 'RET']),
+                            'consentDate'   => $this->faker->date('Y-m-d H:i:s'),
+                            'recipientType' => $this->faker->randomElement(['BIREYSEL', 'TACIR']),
+                            'retailerCode'  => null,
+                            'retailerAccess'=> null,
+                        ],
+                    ],
+                ],
+            ],
+        ];
+
+        $iysAddress = new Add();
+        $iysAddress->setDefaults($data['json']['body']['data'][0]);
+
+        $this->httpClient
+            ->shouldReceive('request')
+            ->withSomeOfArgs('POST', 'iys/add', $data)
+            ->once()
+            ->andReturn(new Response());
+
+        $this->netgsm->iys()->addAddress($iysAddress)->send();
+    }
+
+    /** @test */
+    public function it_makes_search_requests_for_iys_addresses()
+    {
+        $data = [
+            'headers' => [
+                'Content-Type'      => 'application/json',
+            ],
+            'json'    => [
+                'header'    => [
+                    'username'      => 'test',
+                    'password'      => 'test',
+                    'brandCode'     => 123456,
+                ],
+                'body'      => [
+                    'data'      => [
+                        [
+                            'type'          => $this->faker->randomElement(['MESAJ', 'ARAMA']),
+                            'recipient'     => $this->faker->numerify('+905#########'),
+                            'recipientType' => $this->faker->randomElement(['BIREYSEL', 'TACIR']),
+                            'refid'         => $this->faker->numerify('####'),
+                        ],
+                    ],
+                ],
+            ],
+        ];
+
+        $iysSearch = new Search();
+        $iysSearch->setDefaults($data['json']['body']['data'][0]);
+
+        $this->httpClient
+            ->shouldReceive('request')
+            ->withSomeOfArgs('POST', 'iys/search', $data)
+            ->once()
+            ->andReturn(new Response());
+
+        $this->netgsm->iys()->searchAddress($iysSearch)->send();
+    }
+}