diff --git a/ChangeLog b/ChangeLog
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,7 @@
+2013-09-06 v3.0.0
+	* Supporting the sandbox of cabal 1.18.
+	* Obsoleting the support for cabal-dev
+
 2013-09-04 v2.1.2
 	* Supporting multiple target files. (@nh2)
 
diff --git a/Language/Haskell/GhcMod/Browse.hs b/Language/Haskell/GhcMod/Browse.hs
--- a/Language/Haskell/GhcMod/Browse.hs
+++ b/Language/Haskell/GhcMod/Browse.hs
@@ -19,6 +19,7 @@
 
 -- | Getting functions, classes, etc from a module.
 --   If 'detailed' is 'True', their types are also obtained.
+--   If 'operators' is 'True', operators are also returned.
 browseModule :: Options
              -> ModuleString -- ^ A module name. (e.g. \"Data.List\")
              -> IO String
@@ -38,6 +39,7 @@
 
 -- | Getting functions, classes, etc from a module.
 --   If 'detailed' is 'True', their types are also obtained.
+--   If 'operators' is 'True', operators are also returned.
 browse :: Options
        -> ModuleString -- ^ A module name. (e.g. \"Data.List\")
        -> Ghc [String]
diff --git a/Language/Haskell/GhcMod/Check.hs b/Language/Haskell/GhcMod/Check.hs
--- a/Language/Haskell/GhcMod/Check.hs
+++ b/Language/Haskell/GhcMod/Check.hs
@@ -16,7 +16,7 @@
 --   Warnings and errors are returned.
 checkSyntax :: Options
             -> Cradle
-            -> [FilePath]  -- ^ The target files
+            -> [FilePath]  -- ^ The target files.
             -> IO String
 checkSyntax _   _      []    = error "ghc-mod: checkSyntax: No files given"
 checkSyntax opt cradle files = unlines <$> withGHC sessionName (check opt cradle files)
@@ -31,7 +31,7 @@
 --   Warnings and errors are returned.
 check :: Options
       -> Cradle
-      -> [FilePath]  -- ^ The target files
+      -> [FilePath]  -- ^ The target files.
       -> Ghc [String]
 check _   _      []        = error "ghc-mod: check: No files given"
 check opt cradle fileNames = checkIt `gcatch` handleErrMsg ls
diff --git a/Language/Haskell/GhcMod/Cradle.hs b/Language/Haskell/GhcMod/Cradle.hs
--- a/Language/Haskell/GhcMod/Cradle.hs
+++ b/Language/Haskell/GhcMod/Cradle.hs
@@ -2,19 +2,24 @@
 
 import Control.Applicative ((<$>))
 import Control.Exception (throwIO)
-import Control.Monad
+import Control.Monad (unless, filterM)
 import Data.List (isSuffixOf)
+import Distribution.System (buildPlatform)
+import qualified Distribution.Text as Text (display)
 import Language.Haskell.GhcMod.Types
-import System.Directory
+import System.Directory (getCurrentDirectory, getDirectoryContents, doesFileExist, doesDirectoryExist)
 import System.FilePath ((</>),takeDirectory)
 
+----------------------------------------------------------------
+
 -- | Finding 'Cradle'.
 --   An error would be thrown.
-findCradle :: Maybe FilePath -- ^ A 'FilePath' for a sandbox
+findCradle :: Maybe FilePath -- ^ A 'FilePath' for a sandbox.
            -> GHCVersion
            -> IO Cradle
 findCradle (Just sbox) strver = do
-    pkgConf <- checkPackageConf sbox strver
+    (pkgConf,exist) <- checkPackageConf sbox strver
+    unless exist $  throwIO $ userError $ pkgConf ++ " not found"
     wdir <- getCurrentDirectory
     cfiles <- cabalDir wdir
     return $ case cfiles of
@@ -24,7 +29,7 @@
           , cradleCabalFile   = Nothing
           , cradlePackageConf = Just pkgConf
           }
-        Just (cdir,cfile) -> Cradle {
+        Just (cdir,cfile,_) -> Cradle {
             cradleCurrentDir  = wdir
           , cradleCabalDir    = Just cdir
           , cradleCabalFile   = Just cfile
@@ -40,18 +45,36 @@
           , cradleCabalFile   = Nothing
           , cradlePackageConf = Nothing
           }
-        Just (cdir,cfile) -> do
-            let sbox = cdir </> "cabal-dev"
-                pkgConf = packageConfName sbox strver
-            exist <- doesDirectoryExist pkgConf
+        Just (cdir,cfile,Nothing) -> do
             return Cradle {
                 cradleCurrentDir  = wdir
               , cradleCabalDir    = Just cdir
               , cradleCabalFile   = Just cfile
+              , cradlePackageConf = Nothing
+              }
+        Just (cdir,cfile,Just sbox) -> do
+            (pkgConf,exist) <- checkPackageConf sbox strver
+            return Cradle {
+                cradleCurrentDir  = wdir
+              , cradleCabalDir    = Just cdir
+              , cradleCabalFile   = Just cfile
               , cradlePackageConf = if exist then Just pkgConf else Nothing
               }
 
-cabalDir :: FilePath -> IO (Maybe (FilePath,FilePath))
+----------------------------------------------------------------
+
+cabalSuffix :: String
+cabalSuffix = ".cabal"
+
+cabalSuffixLength :: Int
+cabalSuffixLength = length cabalSuffix
+
+-- Finding a Cabal file up to the root directory
+-- Input: a directly to investigate
+-- Output: (the path to the directory containing a Cabal file
+--         ,the path to the Cabal file
+--         ,Just the path to the sandbox directory)
+cabalDir :: FilePath -> IO (Maybe (FilePath,FilePath,Maybe FilePath))
 cabalDir dir = do
     cnts <- (filter isCabal <$> getDirectoryContents dir)
             >>= filterM (\file -> doesFileExist (dir </> file))
@@ -59,18 +82,42 @@
     case cnts of
         [] | dir' == dir -> return Nothing
            | otherwise   -> cabalDir dir'
-        cfile:_          -> return $ Just (dir,dir </> cfile)
+        cfile:_          -> do
+            msbox <- checkSandbox dir
+            return $ Just (dir,dir </> cfile, msbox)
   where
-    isCabal name = ".cabal" `isSuffixOf` name && length name > 6
+    isCabal name = cabalSuffix `isSuffixOf` name
+                && length name > cabalSuffixLength
 
-packageConfName :: FilePath -> String -> FilePath
-packageConfName path ver = path </> "packages-" ++ ver ++ ".conf"
+----------------------------------------------------------------
 
-checkPackageConf :: FilePath -> String -> IO FilePath
-checkPackageConf path ver = do
-    let conf = packageConfName path ver
-    exist <- doesDirectoryExist conf
-    if exist then
-        return conf
+sandboxConfig :: String
+sandboxConfig = "cabal.sandbox.config"
+
+sandboxDir :: String
+sandboxDir = ".cabal-sandbox"
+
+checkSandbox :: FilePath -> IO (Maybe FilePath)
+checkSandbox dir = do
+    let conf = dir </> sandboxConfig
+        sbox = dir </> sandboxDir
+    sandboxConfigExists <- doesFileExist conf
+    sandboxExists <- doesDirectoryExist sbox
+    if sandboxConfigExists && sandboxExists then
+        return (Just sbox)
       else
-        throwIO $ userError $ conf ++ " not found"
+        return Nothing
+
+----------------------------------------------------------------
+
+packageConfName :: GHCVersion -> FilePath
+packageConfName strver = Text.display buildPlatform
+                      ++ "-ghc-"
+                      ++ strver
+                      ++ "-packages.conf.d"
+
+checkPackageConf :: FilePath -> GHCVersion -> IO (FilePath, Bool)
+checkPackageConf path strver = do
+    let dir = path </> packageConfName strver
+    exist <- doesDirectoryExist dir
+    return (dir,exist)
diff --git a/Language/Haskell/GhcMod/Debug.hs b/Language/Haskell/GhcMod/Debug.hs
--- a/Language/Haskell/GhcMod/Debug.hs
+++ b/Language/Haskell/GhcMod/Debug.hs
@@ -18,7 +18,7 @@
 debugInfo :: Options
           -> Cradle
           -> GHCVersion
-          -> FilePath   -- ^ A target file
+          -> FilePath   -- ^ A target file.
           -> IO String
 debugInfo opt cradle ver fileName = unlines <$> withGHC fileName (debug opt cradle ver fileName)
 
@@ -26,7 +26,7 @@
 debug :: Options
       -> Cradle
       -> GHCVersion
-      -> FilePath     -- ^ A target file
+      -> FilePath     -- ^ A target file.
       -> Ghc [String]
 debug opt cradle ver fileName = do
     (gopts, incDir, pkgs) <-
diff --git a/Language/Haskell/GhcMod/ErrMsg.hs b/Language/Haskell/GhcMod/ErrMsg.hs
--- a/Language/Haskell/GhcMod/ErrMsg.hs
+++ b/Language/Haskell/GhcMod/ErrMsg.hs
@@ -22,7 +22,7 @@
 
 ----------------------------------------------------------------
 
--- | A means to read the log
+-- | A means to read the log.
 type LogReader = IO [String]
 
 ----------------------------------------------------------------
diff --git a/Language/Haskell/GhcMod/GHCApi.hs b/Language/Haskell/GhcMod/GHCApi.hs
--- a/Language/Haskell/GhcMod/GHCApi.hs
+++ b/Language/Haskell/GhcMod/GHCApi.hs
@@ -32,13 +32,13 @@
 ----------------------------------------------------------------
 
 -- | Converting the 'Ghc' monad to the 'IO' monad.
-withGHCDummyFile :: Alternative m => Ghc (m a) -- ^ 'Ghc' actions created by the Ghc utilities
+withGHCDummyFile :: Alternative m => Ghc (m a) -- ^ 'Ghc' actions created by the Ghc utilities.
                                   -> IO (m a)
 withGHCDummyFile = withGHC "Dummy"
 
 -- | Converting the 'Ghc' monad to the 'IO' monad.
-withGHC :: Alternative m => FilePath  -- ^ A target file displayed in an error message
-                         -> Ghc (m a) -- ^ 'Ghc' actions created by the Ghc utilities
+withGHC :: Alternative m => FilePath  -- ^ A target file displayed in an error message.
+                         -> Ghc (m a) -- ^ 'Ghc' actions created by the Ghc utilities.
                          -> IO (m a)
 withGHC file body = ghandle ignore $ runGhc (Just libdir) $ do
     dflags <- getSessionDynFlags
@@ -154,7 +154,7 @@
 
 ----------------------------------------------------------------
 
--- | Set the files that GHC will load / compile
+-- | Set the files that GHC will load / compile.
 setTargetFiles :: (GhcMonad m) => [String] -> m ()
 setTargetFiles [] = error "ghc-mod: setTargetFiles: No target files given"
 setTargetFiles files = do
@@ -163,7 +163,7 @@
 
 ----------------------------------------------------------------
 
--- | Return the 'DynFlags' currently in use in the GHC session
+-- | Return the 'DynFlags' currently in use in the GHC session.
 getDynamicFlags :: IO DynFlags
 getDynamicFlags = runGhc (Just libdir) getSessionDynFlags
 
diff --git a/Language/Haskell/GhcMod/Info.hs b/Language/Haskell/GhcMod/Info.hs
--- a/Language/Haskell/GhcMod/Info.hs
+++ b/Language/Haskell/GhcMod/Info.hs
@@ -42,18 +42,18 @@
 -- | Obtaining information of a target expression. (GHCi's info:)
 infoExpr :: Options
          -> Cradle
-         -> FilePath     -- ^ A target file
-         -> ModuleString -- ^ A module name
-         -> Expression   -- ^ A Haskell expression
+         -> FilePath     -- ^ A target file.
+         -> ModuleString -- ^ A module name.
+         -> Expression   -- ^ A Haskell expression.
          -> IO String
 infoExpr opt cradle file modstr expr = (++ "\n") <$> withGHCDummyFile (info opt cradle file modstr expr)
 
 -- | Obtaining information of a target expression. (GHCi's info:)
 info :: Options
      -> Cradle
-     -> FilePath     -- ^ A target file
-     -> ModuleString -- ^ A module name
-     -> Expression   -- ^ A Haskell expression
+     -> FilePath     -- ^ A target file.
+     -> ModuleString -- ^ A module name.
+     -> Expression   -- ^ A Haskell expression.
      -> Ghc String
 info opt cradle file modstr expr =
     inModuleContext Info opt cradle file modstr exprToInfo "Cannot show info"
@@ -83,20 +83,20 @@
 -- | Obtaining type of a target expression. (GHCi's type:)
 typeExpr :: Options
          -> Cradle
-         -> FilePath     -- ^ A target file
-         -> ModuleString -- ^ A odule name
-         -> Int          -- ^ Line number
-         -> Int          -- ^ Column number
+         -> FilePath     -- ^ A target file.
+         -> ModuleString -- ^ A odule name.
+         -> Int          -- ^ Line number.
+         -> Int          -- ^ Column number.
          -> IO String
 typeExpr opt cradle file modstr lineNo colNo = withGHCDummyFile $ typeOf opt cradle file modstr lineNo colNo
 
 -- | Obtaining type of a target expression. (GHCi's type:)
 typeOf :: Options
        -> Cradle
-       -> FilePath     -- ^ A target file
-       -> ModuleString -- ^ A odule name
-       -> Int          -- ^ Line number
-       -> Int          -- ^ Column number
+       -> FilePath     -- ^ A target file.
+       -> ModuleString -- ^ A odule name.
+       -> Int          -- ^ Line number.
+       -> Int          -- ^ Column number.
        -> Ghc String
 typeOf opt cradle file modstr lineNo colNo =
     inModuleContext Type opt cradle file modstr exprToType errmsg
diff --git a/Language/Haskell/GhcMod/Types.hs b/Language/Haskell/GhcMod/Types.hs
--- a/Language/Haskell/GhcMod/Types.hs
+++ b/Language/Haskell/GhcMod/Types.hs
@@ -3,15 +3,17 @@
 module Language.Haskell.GhcMod.Types where
 
 -- | Output style.
-data OutputStyle = LispStyle  -- ^ S expression style
-                 | PlainStyle -- ^ Plain textstyle
+data OutputStyle = LispStyle  -- ^ S expression style.
+                 | PlainStyle -- ^ Plain textstyle.
 
+-- | The type for line separator. Historically, a Null string is used.
 newtype LineSeparator = LineSeparator String
 
 data Options = Options {
     outputStyle   :: OutputStyle
   , hlintOpts     :: [String]
   , ghcOpts       :: [String]
+  -- | If 'True', 'browse' also returns operators.
   , operators     :: Bool
   -- | If 'True', 'browse' also returns types.
   , detailed      :: Bool
@@ -19,6 +21,7 @@
   , expandSplice  :: Bool
   -- | The sandbox directory.
   , sandbox       :: Maybe FilePath
+  -- | Line separator string.
   , lineSeparator :: LineSeparator
   }
 
@@ -74,33 +77,33 @@
 
 ----------------------------------------------------------------
 
--- | The environment where this library is used
+-- | The environment where this library is used.
 data Cradle = Cradle {
-  -- | The directory where this library is executed
+  -- | The directory where this library is executed.
     cradleCurrentDir  :: FilePath
-  -- | The directory where a cabal file is found
+  -- | The directory where a cabal file is found.
   , cradleCabalDir    :: Maybe FilePath
-  -- | The file name of the found cabal file
+  -- | The file name of the found cabal file.
   , cradleCabalFile   :: Maybe FilePath
-  -- | The sandbox directory (e.g. \"\/foo\/bar\/packages-\<ver\>.conf/\")
+  -- | The sandbox directory. (e.g. \"\/foo\/bar\/packages-\<ver\>.conf/\")
   , cradlePackageConf :: Maybe FilePath
   } deriving (Eq, Show)
 
 ----------------------------------------------------------------
 
--- | A single GHC option, as it would appear on the command line
+-- | A single GHC option, as it would appear on the command line.
 type GHCOption  = String
 
 type IncludeDir = FilePath
 type Package    = String
 
--- | GHC version in 'String'
+-- | GHC version in 'String'.
 type GHCVersion = String
 
--- | Haskell expression
+-- | Haskell expression.
 type Expression = String
 
--- | Module name
+-- | Module name.
 type ModuleString = String
 
 data CheckSpeed = Slow | Fast
diff --git a/ghc-mod.cabal b/ghc-mod.cabal
--- a/ghc-mod.cabal
+++ b/ghc-mod.cabal
@@ -1,5 +1,5 @@
 Name:                   ghc-mod
-Version:                2.1.2
+Version:                3.0.0
 Author:                 Kazu Yamamoto <kazu@iij.ad.jp>
 Maintainer:             Kazu Yamamoto <kazu@iij.ad.jp>
 License:                BSD3
@@ -26,7 +26,8 @@
 Extra-Source-Files:     ChangeLog
 			test/data/*.cabal
                         test/data/*.hs
-                        test/data/cabal-dev/packages-7.6.2.conf/dummy
+                        test/data/cabal.sandbox.config
+                        test/data/.cabal-sandbox/i386-osx-ghc-7.6.3-packages.conf.d/dummy
                         test/data/ghc-mod-check/*.hs
                         test/data/ghc-mod-check/*.cabal
                         test/data/ghc-mod-check/Data/*.hs
diff --git a/src/GHCMod.hs b/src/GHCMod.hs
--- a/src/GHCMod.hs
+++ b/src/GHCMod.hs
@@ -57,7 +57,7 @@
             "print detailed info"
           , Option "s" ["sandbox"]
             (ReqArg (\s opts -> opts { sandbox = Just s }) "path")
-            "specify cabal-dev sandbox (default 'cabal-dev`)"
+            "specify a sandbox"
           , Option "b" ["boundary"]
             (ReqArg (\s opts -> opts { lineSeparator = LineSeparator s }) "sep")
             "specify line separator (default is Nul string)"
diff --git a/test/data/.cabal-sandbox/i386-osx-ghc-7.6.3-packages.conf.d/dummy b/test/data/.cabal-sandbox/i386-osx-ghc-7.6.3-packages.conf.d/dummy
new file mode 100644
--- /dev/null
+++ b/test/data/.cabal-sandbox/i386-osx-ghc-7.6.3-packages.conf.d/dummy
@@ -0,0 +1,1 @@
+dummy
diff --git a/test/data/cabal-dev/packages-7.6.2.conf/dummy b/test/data/cabal-dev/packages-7.6.2.conf/dummy
deleted file mode 100644
--- a/test/data/cabal-dev/packages-7.6.2.conf/dummy
+++ /dev/null
@@ -1,1 +0,0 @@
-dummy
diff --git a/test/data/cabal.sandbox.config b/test/data/cabal.sandbox.config
new file mode 100644
--- /dev/null
+++ b/test/data/cabal.sandbox.config
@@ -0,0 +1,25 @@
+-- This is a Cabal package environment file.
+-- THIS FILE IS AUTO-GENERATED. DO NOT EDIT DIRECTLY.
+-- Please create a 'cabal.config' file in the same directory
+-- if you want to change the default settings for this sandbox.
+
+
+local-repo: /Users/kazu/work/ghc-mod/test/data/.cabal-sandbox/packages
+logs-dir: /Users/kazu/work/ghc-mod/test/data/.cabal-sandbox/logs
+world-file: /Users/kazu/work/ghc-mod/test/data/.cabal-sandbox/world
+user-install: False
+package-db: /Users/kazu/work/ghc-mod/test/data/.cabal-sandbox/i386-osx-ghc-7.6.3-packages.conf.d
+build-summary: /Users/kazu/work/ghc-mod/test/data/.cabal-sandbox/logs/build.log
+
+install-dirs 
+  prefix: /Users/kazu/work/ghc-mod/test/data/.cabal-sandbox
+  bindir: $prefix/bin
+  libdir: $prefix/lib
+  libsubdir: $arch-$os-$compiler/$pkgid
+  libexecdir: $prefix/libexec
+  datadir: $prefix/share
+  datasubdir: $arch-$os-$compiler/$pkgid
+  docdir: $datadir/doc/$arch-$os-$compiler/$pkgid
+  htmldir: $docdir/html
+  haddockdir: $htmldir
+  sysconfdir: $prefix/etc