diff --git a/src/main/resources/reference.conf b/src/main/resources/reference.conf
index 2456949..124ed69 100644
--- a/src/main/resources/reference.conf
+++ b/src/main/resources/reference.conf
@@ -19,6 +19,9 @@ gitlab-template {
 
       // Pagination value for Gitlab. See https://docs.gitlab.com/ee/api/README.html#pagination for details.
       per-page: 100
+
+      // throttle interval (milliseconds)
+      throttle-duration: 100
     }
 
     technical-users-keys {
diff --git a/src/main/scala/de/frosner/gitlabtemplate/GitlabSource.scala b/src/main/scala/de/frosner/gitlabtemplate/GitlabSource.scala
index 689d053..bf15a75 100644
--- a/src/main/scala/de/frosner/gitlabtemplate/GitlabSource.scala
+++ b/src/main/scala/de/frosner/gitlabtemplate/GitlabSource.scala
@@ -34,7 +34,8 @@ class GitlabSource(wsClient: StandaloneWSClient,
                    url: String,
                    privateToken: String,
                    onlyActiveUsers: Boolean,
-                   perPage: Int)(implicit ec: ExecutionContext, materializer: Materializer)
+                   perPage: Int,
+                   throttleDuration: Long)(implicit ec: ExecutionContext, materializer: Materializer)
     extends StrictLogging {
 
   def getUsers: EitherT[Future, Error, Set[GitlabUser]] = {
@@ -67,6 +68,7 @@ class GitlabSource(wsClient: StandaloneWSClient,
             .url(s"$url/api/v4/users/${user.id}/keys")
             .withHttpHeaders(("PRIVATE-TOKEN", privateToken))
           logger.debug(s"Requesting public keys for ${user.username}: ${request.url}")
+          Thread.sleep(throttleDuration)
           request.get().map { response =>
             Json
               .fromJson[Set[PublicKey]](response.body[JsValue])
diff --git a/src/main/scala/de/frosner/gitlabtemplate/GitlabTemplateConfig.scala b/src/main/scala/de/frosner/gitlabtemplate/GitlabTemplateConfig.scala
index d52a967..c6372d8 100644
--- a/src/main/scala/de/frosner/gitlabtemplate/GitlabTemplateConfig.scala
+++ b/src/main/scala/de/frosner/gitlabtemplate/GitlabTemplateConfig.scala
@@ -22,6 +22,6 @@ case class PrivateTokenAuthConfig(enabled: Boolean, token: String)
 
 case class SinkConfig(filesystem: FilesystemConfig)
 
-case class GitlabConfig(onlyActiveUsers: Boolean, privateToken: String, url: String, perPage: Int)
+case class GitlabConfig(onlyActiveUsers: Boolean, privateToken: String, url: String, perPage: Int, throttleDuration: Long)
 
 case class FilesystemConfig(path: Path, publicKeysFile: String, createEmptyKeyFile: Boolean)
diff --git a/src/main/scala/de/frosner/gitlabtemplate/Main.scala b/src/main/scala/de/frosner/gitlabtemplate/Main.scala
index 67fc27d..49030a2 100644
--- a/src/main/scala/de/frosner/gitlabtemplate/Main.scala
+++ b/src/main/scala/de/frosner/gitlabtemplate/Main.scala
@@ -51,7 +51,8 @@ object Main extends StrictLogging {
                          gitlabConf.url,
                          gitlabConf.privateToken,
                          gitlabConf.onlyActiveUsers,
-                         gitlabConf.perPage)
+                         gitlabConf.perPage,
+                         gitlabConf.throttleDuration)
 
       val technicalUsersKeysSource =
         new TechnicalUsersKeysSource(wsClient,
diff --git a/src/test/scala/de/frosner/gitlabtemplate/GitlabSourceSpec.scala b/src/test/scala/de/frosner/gitlabtemplate/GitlabSourceSpec.scala
index 701bbad..a810020 100644
--- a/src/test/scala/de/frosner/gitlabtemplate/GitlabSourceSpec.scala
+++ b/src/test/scala/de/frosner/gitlabtemplate/GitlabSourceSpec.scala
@@ -48,7 +48,7 @@ class GitlabSourceSpec extends FlatSpec with Matchers with HttpTests {
             GitlabUser(1, "usr1"),
             GitlabUser(2, "usr2")
           )
-          new GitlabSource(wsClient, address, "token", false, 100).getUsers.value
+          new GitlabSource(wsClient, address, "token", false, 100, 1).getUsers.value
             .map(_ shouldBe Right(expected))
       }
     }
@@ -76,7 +76,7 @@ class GitlabSourceSpec extends FlatSpec with Matchers with HttpTests {
             GitlabUser(6, "usr6"),
             GitlabUser(7, "usr7")
           )
-          new GitlabSource(wsClient, address, "token", false, 2).getUsers.value
+          new GitlabSource(wsClient, address, "token", false, 2, 1).getUsers.value
             .map(_ shouldBe Right(expected))
       }
     }
@@ -97,7 +97,7 @@ class GitlabSourceSpec extends FlatSpec with Matchers with HttpTests {
     } { implicit ec => implicit materializer =>
       {
         case (wsClient, address) =>
-          new GitlabSource(wsClient, address, "token", false, 100).getUsers.value
+          new GitlabSource(wsClient, address, "token", false, 100, 1).getUsers.value
             .map(_ shouldBe a[Left[_, _]])
       }
     }
@@ -107,7 +107,7 @@ class GitlabSourceSpec extends FlatSpec with Matchers with HttpTests {
     withServerAndClient { RouteDirectives.reject } { implicit ec => implicit materializer =>
       {
         case (wsClient, address) =>
-          new GitlabSource(wsClient, "http://dsafdsgdfsfdsfdsf", "token", false, 100).getUsers.value.failed
+          new GitlabSource(wsClient, "http://dsafdsgdfsfdsfdsf", "token", false, 100, 1).getUsers.value.failed
             .map(_ shouldBe a[UnknownHostException])
       }
     }
@@ -135,7 +135,7 @@ class GitlabSourceSpec extends FlatSpec with Matchers with HttpTests {
             "usr1" -> Set("key1", "key2"),
             "usr2" -> Set("key3")
           )
-          new GitlabSource(wsClient, address, "token", false, 100)
+          new GitlabSource(wsClient, address, "token", false, 100, 1)
             .getSshKeys(users)
             .value
             .map(_ shouldBe Right(expected))
@@ -153,7 +153,7 @@ class GitlabSourceSpec extends FlatSpec with Matchers with HttpTests {
     } { implicit ec => implicit materializer =>
       {
         case (wsClient, address) =>
-          new GitlabSource(wsClient, address, "token", false, 100)
+          new GitlabSource(wsClient, address, "token", false, 100, 1)
             .getSshKeys(Set(GitlabUser(1, "usr1")))
             .value
             .map(_ shouldBe a[Left[_, _]])
@@ -165,7 +165,7 @@ class GitlabSourceSpec extends FlatSpec with Matchers with HttpTests {
     withServerAndClient { RouteDirectives.reject } { implicit ec => implicit materializer =>
       {
         case (wsClient, address) =>
-          new GitlabSource(wsClient, address, "token", false, 100)
+          new GitlabSource(wsClient, address, "token", false, 100, 1)
             .getSshKeys(Set(GitlabUser(1, "usr1")))
             .value
             .failed