diff --git a/core/src/main/java/co/aikar/commands/CommandManager.java b/core/src/main/java/co/aikar/commands/CommandManager.java
index 80c1ae9e..680744d4 100644
--- a/core/src/main/java/co/aikar/commands/CommandManager.java
+++ b/core/src/main/java/co/aikar/commands/CommandManager.java
@@ -76,7 +76,7 @@ public abstract class CommandManager<
 
     protected boolean usePerIssuerLocale = false;
     protected List<IssuerLocaleChangedCallback<I>> localeChangedCallbacks = new ArrayList<>();
-    protected Set<Locale> supportedLanguages = new HashSet<>(Arrays.asList(Locales.ENGLISH, Locales.GERMAN, Locales.SPANISH, Locales.FRENCH, Locales.CZECH, Locales.PORTUGUESE, Locales.SWEDISH, Locales.NORWEGIAN_BOKMAAL, Locales.NORWEGIAN_NYNORSK, Locales.RUSSIAN, Locales.BULGARIAN, Locales.HUNGARIAN, Locales.TURKISH));
+    protected Set<Locale> supportedLanguages = new HashSet<>(Arrays.asList(Locales.ENGLISH, Locales.GERMAN, Locales.SPANISH, Locales.FRENCH, Locales.CZECH, Locales.PORTUGUESE, Locales.SWEDISH, Locales.NORWEGIAN_BOKMAAL, Locales.NORWEGIAN_NYNORSK, Locales.RUSSIAN, Locales.BULGARIAN, Locales.HUNGARIAN, Locales.TURKISH, Locales.JAPANESE));
     protected Map<MessageType, MF> formatters = new IdentityHashMap<>();
     protected MF defaultFormatter;
     protected int defaultHelpPerPage = 10;
diff --git a/languages/core/acf-core_ja.properties b/languages/core/acf-core_ja.properties
new file mode 100644
index 00000000..06715c11
--- /dev/null
+++ b/languages/core/acf-core_ja.properties
@@ -0,0 +1,46 @@
+# Copyright (c) 2016-2017 Daniel Ennis (Aikar) - MIT License
+#
+#  Permission is hereby granted, free of charge, to any person obtaining
+#  a copy of this software and associated documentation files (the
+#  "Software"), to deal in the Software without restriction, including
+#  without limitation the rights to use, copy, modify, merge, publish,
+#  distribute, sublicense, and/or sell copies of the Software, and to
+#  permit persons to whom the Software is furnished to do so, subject to
+#  the following conditions:
+#
+#  The above copyright notice and this permission notice shall be
+#  included in all copies or substantial portions of the Software.
+#
+#  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+#  EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+#  MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+#  NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+#  LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+#  OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+#  WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+#
+acf-core.permission_denied=申し訳ありません, このコマンドを実行する権限がありません.
+acf-core.permission_denied_parameter=申し訳ありません, このコマンドを実行する権限がありません.
+acf-core.error_generic_logged=エラーが発生しました. この問題はログに記録されました. ご迷惑をおかけして申し訳ありません.
+acf-core.unknown_command=不明なコマンドです. <c2>/help</c2>と入力してください.
+acf-core.invalid_syntax=使用方法: <c2>{command}</c2> <c3>{syntax}</c3>
+acf-core.error_prefix=エラー: {message}
+acf-core.error_performing_command=申し訳ありません, コマンドの実行中にエラーが発生しました.
+acf-core.info_message={message}
+acf-core.please_specify_one_of=エラー: 次のいずれかを指定してください (<c2>{valid}</c2>).
+acf-core.must_be_a_number=エラー: {num} は数値である必要があります.
+acf-core.must_be_min_length=エラー: 最小 {min} 文字以上である必要があります.
+acf-core.must_be_max_length=エラー: 最大 {max} 文字以下である必要があります.
+acf-core.please_specify_at_most=エラー: 最大 {max} までの値を指定してください.
+acf-core.please_specify_at_least=エラー: 最小 {min} までの値を指定してください.
+acf-core.not_allowed_on_console=エラー: コンソールはこのコマンドを実行できません.
+acf-core.could_not_find_player=エラー: 名前のプレイヤーが見つかりませんでした: <c2>{search}</c2>
+acf-core.no_command_matched_search=一致するコマンドがありません <c2>{search}</c2>.
+acf-core.help_page_information=- <c2>{totalpages}</c2> ページ中 <c2>{page}</c2> ページを表示中 (<c3>{results}</c3> 件).
+acf-core.help_no_results=エラー: これ以上結果はありません.
+acf-core.help_header=<c3>=== </c3><c2>{commandprefix}{command}</c2><c1> のヘルプを表示中</c1><c3> ===</c3>
+acf-core.help_format=<c1>{command}</c1> <c2>{parameters}</c2> <c3>{separator} {description}</c3>
+acf-core.help_detailed_header=<c3>=== </c3><c2>{commandprefix}{command}</c2><c1> の詳細なヘルプを表示中</c1><c3> ===</c3>
+acf-core.help_detailed_command_format=<c1>{command}</c1> <c2>{parameters}</c2> <c3>{separator} {description}</c3>
+acf-core.help_detailed_parameter_format=<c2>{syntaxorname}</c2>: <c3>{description}</c3>
+acf-core.help_search_header=<c3>=== </c3><c2>{commandprefix}{command} {search}</c2><c1> の検索結果</c1><c3> ===</c3>
diff --git a/languages/minecraft/acf-minecraft_ja.properties b/languages/minecraft/acf-minecraft_ja.properties
new file mode 100644
index 00000000..3c0dcb91
--- /dev/null
+++ b/languages/minecraft/acf-minecraft_ja.properties
@@ -0,0 +1,38 @@
+#
+# Copyright (c) 2016-2017 Daniel Ennis (Aikar) - MIT License
+#
+#  Permission is hereby granted, free of charge, to any person obtaining
+#  a copy of this software and associated documentation files (the
+#  "Software"), to deal in the Software without restriction, including
+#  without limitation the rights to use, copy, modify, merge, publish,
+#  distribute, sublicense, and/or sell copies of the Software, and to
+#  permit persons to whom the Software is furnished to do so, subject to
+#  the following conditions:
+#
+#  The above copyright notice and this permission notice shall be
+#  included in all copies or substantial portions of the Software.
+#
+#  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+#  EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+#  MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+#  NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+#  LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+#  OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+#  WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+#
+
+acf-minecraft.invalid_world = エラー: そのワールドは存在しません.
+acf-minecraft.you_must_be_holding_item = エラー: アイテムをメインハンドで持つ必要があります.
+acf-minecraft.player_is_vanished_confirm = \
+    警告: <c2>{vanished}</c2> は不可視状態です. 化けの皮を剥がさないで!\n\
+    実行するには, <c2>:confirm</c2> を名前の最後に加えてください.\n\
+    例: <c2>{vanished}:confirm</c2>
+acf-minecraft.username_too_short = エラー: ユーザー名が短すぎます, 3文字以上で入力してください.
+acf-minecraft.is_not_a_valid_name = エラー: <c2>{name}</c2> は正しいユーザー名ではありません.
+acf-minecraft.multiple_players_match = エラー: 複数のプレイヤーが一致しました <c2>{search}</c2> <c3>({all})</c3>, さらに詳細に入力してください.
+acf-minecraft.no_player_found_server = <c2>{search}</c2> に一致するプレイヤーがこのサーバーに接続していません.
+acf-minecraft.no_player_found_offline = <c2>{search}</c2> に一致するプレイヤーが見つかりません.
+acf-minecraft.no_player_found = <c2>{search}</c2> に一致するプレイヤーが見つかりません.
+acf-minecraft.location_please_specify_world = エラー: ワールドを指定してください. 例: <c2>world:x,y,z</c2>.
+acf-minecraft.location_please_specify_xyz = エラー: x, y, z座標を指定してください. 例: <c2>world:x,y,z</c2>.
+acf-minecraft.location_console_not_relative = エラー: コンソールでは位置情報に相対座標を使用できません.