diff --git a/ChangeLog.md b/ChangeLog.md
--- a/ChangeLog.md
+++ b/ChangeLog.md
@@ -1,3 +1,7 @@
+## 0.1.5
+
+* Add the function of changing environment-variables and working-directory with register-function-arguments.
+
 ## 0.1.4
 
 * Allow '.' and '-' for valid procsss name
diff --git a/src/Test/Sandbox.hs b/src/Test/Sandbox.hs
--- a/src/Test/Sandbox.hs
+++ b/src/Test/Sandbox.hs
@@ -128,13 +128,20 @@
     liftIO $ actions ref
 
 -- | Optional parameters when registering a process in the Sandbox monad.
-data ProcessSettings = ProcessSettings {
+data ProcessSettings =
+  ProcessSettings {
     psWait :: Maybe Int        -- ^ Time to wait (in s.) before checking that the process is still up
   , psCapture :: Maybe Capture -- ^ Which outputs to capture (if any)
+  } |
+  ProcessSettings2 {
+    psWait :: Maybe Int              -- ^ Time to wait (in s.) before checking that the process is still up
+  , psCapture :: Maybe Capture       -- ^ Which outputs to capture (if any)
+  , psEnv :: Maybe [(String,String)] -- ^ Environment variables
+  , psCwd :: Maybe FilePath          -- ^ Working directory for the new process
   }
 
 instance Default ProcessSettings where
-  def = ProcessSettings (Just 1) Nothing
+  def = ProcessSettings2 (Just 1) Nothing Nothing Nothing
 
 -- | Registers a process in the Sandbox monad.
 register :: String          -- ^ Process name
@@ -142,7 +149,10 @@
          -> [String]        -- ^ Arguments to pass on the command-line
          -> ProcessSettings -- ^ Process settings
          -> Sandbox String
-register name bin args params = registerProcess name bin args (psWait params) (psCapture params) >> return name
+register name bin args (ProcessSettings wait capture) =
+  registerProcess name bin args wait capture Nothing Nothing >> return name
+register name bin args (ProcessSettings2 wait capture env cwd) =
+  registerProcess name bin args wait capture env cwd >> return name
 
 -- | Communicates with a sandboxed process via TCP and returns the answered message as a string.
 sendTo :: String         -- ^ Name of the registered port 
diff --git a/src/Test/Sandbox/Internals.hs b/src/Test/Sandbox/Internals.hs
--- a/src/Test/Sandbox/Internals.hs
+++ b/src/Test/Sandbox/Internals.hs
@@ -51,6 +51,7 @@
 #else
 import System.Process hiding (env, waitForProcess)
 #endif
+import qualified System.Process as P
 import System.Process.Internals (withProcessHandle, ProcessHandle__(OpenHandle))
 import System.Random
 import System.Random.Shuffle
@@ -121,6 +122,8 @@
   , spPid :: Maybe ProcessID
   , spPGid :: Maybe ProcessGroupID
   , spHandles :: [Handle]
+  , spEnvs :: Maybe [(String,String)]
+  , spCwd :: Maybe FilePath
   }
 
 data Capture =
@@ -175,10 +178,15 @@
       -- Do not use these area for "userPorts" to avoid conflict.
   newIORef $ SandboxState name dir M.empty [] M.empty availablePorts M.empty M.empty
 
-registerProcess ::
-  String -> FilePath -> [String] -> Maybe Int -> Maybe Capture
-  -> Sandbox SandboxedProcess
-registerProcess name bin args wait capture = do
+registerProcess :: String                  -- ^ Process Name
+                -> FilePath                -- ^ Path to the application binary
+                -> [String]                -- ^ Arguments to pass on the command-line
+                -> Maybe Int               -- ^ Time to wait (in s.) before checking that the process is still up
+                -> Maybe Capture           -- ^ Which outputs to capture (if any)
+                -> Maybe [(String,String)] -- ^ Evironment variables
+                -> Maybe FilePath          -- ^ Working directory for the new process
+                -> Sandbox SandboxedProcess
+registerProcess name bin args wait capture process_env process_cwd = do
   -- Validate process name
   unless (isValidProcessName name) $
     throwError $ "Invalid process name: " ++ name ++ "."
@@ -186,7 +194,7 @@
   env <- get
   if isJust (M.lookup name (ssProcesses env)) then
     throwError $ "Process " ++ name ++ " is already registered in the test environment."
-    else do let sp = SandboxedProcess name bin args wait capture Nothing Nothing Nothing []
+    else do let sp = SandboxedProcess name bin args wait capture Nothing Nothing Nothing [] process_env process_cwd
             _ <- put env { ssProcesses = M.insert name sp (ssProcesses env)
                          , ssProcessOrder = ssProcessOrder env ++ [name]
                          }
@@ -363,10 +371,13 @@
               hde <- openFile filepath_e WriteMode
               return (Nothing, UseHandle hdo, UseHandle hde, [hdo,hde])
         Nothing -> return (Nothing, Inherit, Inherit, [])
-      (Just ih, _, _, ph) <- liftIO $ createProcess $ (proc bin args) {create_group = True
+      (Just ih, _, _, ph) <- liftIO $ createProcess $ (proc bin args) { create_group = True
                                                                       , std_in = CreatePipe
                                                                       , std_out = hOutRW
-                                                                      , std_err = hErrRW }
+                                                                      , std_err = hErrRW
+                                                                      , cwd = spCwd sp
+                                                                      , P.env = spEnvs sp
+                                                                      }
       when (isJust $ spWait sp) $ do
         liftIO . threadDelay $ fromJust (spWait sp) * secondInµs
       errno <- liftIO $ getProcessExitCode ph
diff --git a/test-sandbox.cabal b/test-sandbox.cabal
--- a/test-sandbox.cabal
+++ b/test-sandbox.cabal
@@ -1,5 +1,5 @@
 Name:           test-sandbox
-Version:        0.1.4
+Version:        0.1.5
 Cabal-Version:  >= 1.14
 Category:       Testing
 Synopsis:       Sandbox for system tests
@@ -28,7 +28,7 @@
 Source-Repository this
     Type:       git
     Location:   https://github.com/gree/haskell-test-sandbox
-    Tag:        test-sandbox_0.1.4
+    Tag:        test-sandbox_0.1.5
 
 Library
     Exposed-modules:    Test.Sandbox