diff --git a/docs/index.rst b/docs/index.rst
index fc363d5271d5..2467260f9745 100644
--- a/docs/index.rst
+++ b/docs/index.rst
@@ -9,6 +9,38 @@
   iterators
   operation-api
 
+.. toctree::
+  :maxdepth: 0
+  :hidden:
+  :caption: BigQuery
+
+  bigquery-usage
+  Client <bigquery-client>
+  bigquery-dataset
+  bigquery-job
+  bigquery-table
+  bigquery-query
+  bigquery-schema
+
+.. toctree::
+  :maxdepth: 0
+  :hidden:
+  :caption: BigTable
+
+  bigtable-usage
+  bigtable-client-intro
+  bigtable-instance-api
+  bigtable-table-api
+  bigtable-data-api
+  Client <bigtable-client>
+  bigtable-instance
+  bigtable-cluster
+  bigtable-table
+  bigtable-column-family
+  bigtable-row
+  bigtable-row-filters
+  bigtable-row-data
+
 .. toctree::
   :maxdepth: 0
   :hidden:
@@ -26,13 +58,23 @@
 .. toctree::
   :maxdepth: 0
   :hidden:
-  :caption: Storage
+  :caption: DNS
 
-  Client <storage-client>
-  storage-blobs
-  storage-buckets
-  storage-acl
-  storage-batch
+  dns-usage
+  Client <dns-client>
+  dns-zone
+  dns-resource-record-set
+  dns-changes
+
+.. toctree::
+  :maxdepth: 0
+  :hidden:
+  :caption: Natural Language
+
+  language-usage
+  Client <language-client>
+  language-document
+  language-responses
 
 .. toctree::
   :maxdepth: 0
@@ -49,54 +91,69 @@
 .. toctree::
   :maxdepth: 0
   :hidden:
-  :caption: BigQuery
+  :caption: Resource Manager
 
-  bigquery-usage
-  Client <bigquery-client>
-  bigquery-dataset
-  bigquery-job
-  bigquery-table
-  bigquery-query
-  bigquery-schema
+  Overview <resource-manager-api>
+  resource-manager-client
+  resource-manager-project
 
 .. toctree::
   :maxdepth: 0
   :hidden:
-  :caption: Cloud Bigtable
+  :caption: Runtime Configuration
 
-  bigtable-usage
-  bigtable-client-intro
-  bigtable-instance-api
-  bigtable-table-api
-  bigtable-data-api
-  Client <bigtable-client>
-  bigtable-instance
-  bigtable-cluster
-  bigtable-table
-  bigtable-column-family
-  bigtable-row
-  bigtable-row-filters
-  bigtable-row-data
+  runtimeconfig-usage
+  Client <runtimeconfig-client>
+  runtimeconfig-config
+  runtimeconfig-variable
 
 .. toctree::
   :maxdepth: 0
   :hidden:
-  :caption: Resource Manager
+  :caption: Spanner
 
-  Overview <resource-manager-api>
-  resource-manager-client
-  resource-manager-project
+  spanner-usage
+  spanner-client-usage
+  spanner-instance-usage
+  spanner-database-usage
+  spanner-session-crud-usage
+  spanner-session-implicit-txn-usage
+  spanner-session-pool-usage
+  spanner-batch-usage
+  spanner-snapshot-usage
+  spanner-transaction-usage
+
+  spanner-client-api
+  spanner-instance-api
+  spanner-database-api
+  spanner-session-api
+  spanner-keyset-api
+  spanner-snapshot-api
+  spanner-batch-api
+  spanner-transaction-api
+  spanner-streamed-api
 
 .. toctree::
   :maxdepth: 0
   :hidden:
-  :caption: DNS
+  :caption: Speech
 
-  dns-usage
-  Client <dns-client>
-  dns-zone
-  dns-resource-record-set
-  dns-changes
+  speech-usage
+  Client <speech-client>
+  speech-encoding
+  speech-operation
+  speech-result
+  speech-sample
+  speech-alternative
+
+.. toctree::
+  :maxdepth: 0
+  :hidden:
+  :caption: Stackdriver Error Reporting
+
+  error-reporting-usage
+  Client <error-reporting-client>
+  error-reporting-util
 
 .. toctree::
   :maxdepth: 0
@@ -117,15 +174,6 @@
   logging-transports-thread
   logging-transports-base
 
-.. toctree::
-  :maxdepth: 0
-  :hidden:
-  :caption: Stackdriver Error Reporting
-
-  error-reporting-usage
-  Client <error-reporting-client>
-  error-reporting-util
-
 .. toctree::
   :maxdepth: 0
   :hidden:
@@ -140,6 +188,17 @@
   monitoring-timeseries
   monitoring-label
 
+.. toctree::
+  :maxdepth: 0
+  :hidden:
+  :caption: Storage
+
+  Client <storage-client>
+  storage-blobs
+  storage-buckets
+  storage-acl
+  storage-batch
+
 .. toctree::
   :maxdepth: 0
   :hidden:
@@ -167,65 +226,6 @@
   vision-text
   vision-web
 
-.. toctree::
-  :maxdepth: 0
-  :hidden:
-  :caption: Natural Language
-
-  language-usage
-  Client <language-client>
-  language-document
-  language-responses
-
-.. toctree::
-  :maxdepth: 0
-  :hidden:
-  :caption: Speech
-
-  speech-usage
-  Client <speech-client>
-  speech-encoding
-  speech-operation
-  speech-result
-  speech-sample
-  speech-alternative
-
-.. toctree::
-  :maxdepth: 0
-  :hidden:
-  :caption: Runtime Configuration
-
-  runtimeconfig-usage
-  Client <runtimeconfig-client>
-  runtimeconfig-config
-  runtimeconfig-variable
-
-.. toctree::
-  :maxdepth: 0
-  :hidden:
-  :caption: Spanner
-
-  spanner-usage
-  spanner-client-usage
-  spanner-instance-usage
-  spanner-database-usage
-  spanner-session-crud-usage
-  spanner-session-implicit-txn-usage
-  spanner-session-pool-usage
-  spanner-batch-usage
-  spanner-snapshot-usage
-  spanner-transaction-usage
-
-  spanner-client-api
-  spanner-instance-api
-  spanner-database-api
-  spanner-session-api
-  spanner-keyset-api
-  spanner-snapshot-api
-  spanner-batch-api
-  spanner-transaction-api
-  spanner-streamed-api
-
 .. toctree::
   :maxdepth: 0
   :hidden: