diff --git a/CHANGELOG b/CHANGELOG
index 79e4dc1bd0..45da171c2b 100644
--- a/CHANGELOG
+++ b/CHANGELOG
@@ -1,5 +1,10 @@
-git-annex (6.20160620) UNRELEASED; urgency=medium
+git-annex (6.20160726) UNRELEASED; urgency=medium
 
+  * metadata --json output format has changed, adding a inner json object
+    named "fields" which contains only the fields and their values.
+    This should be easier to parse than the old format, which mixed up
+    metadata fields with other keys in the json object.
+    Any consumers of the old format will need to be updated.
   * Added --branch option to copy, drop, fsck, get, metadata, mirror, move,
     and whereis commands. This option makes git-annex operate on files that
     are included in a specified branch (or other treeish).
diff --git a/Command/MetaData.hs b/Command/MetaData.hs
index 3123a63d09..66469f2fc9 100644
--- a/Command/MetaData.hs
+++ b/Command/MetaData.hs
@@ -1,6 +1,6 @@
 {- git-annex command
  -
- - Copyright 2014 Joey Hess <id@joeyh.name>
+ - Copyright 2014-2016 Joey Hess <id@joeyh.name>
  -
  - Licensed under the GNU GPL version 3 or higher.
  -}
@@ -10,9 +10,13 @@ module Command.MetaData where
 import Command
 import Annex.MetaData
 import Logs.MetaData
+import Messages.JSON (ParsedJSON(..))
 
 import qualified Data.Set as S
+import qualified Data.Text as T
+import qualified Data.ByteString.Lazy.UTF8 as BU
 import Data.Time.Clock.POSIX
+import Data.Aeson
 
 cmd :: Command
 cmd = withGlobalOptions ([jsonOption] ++ annexedMatchingOptions) $ 
@@ -95,10 +99,38 @@ perform now o k = case getSet o of
 
 cleanup :: Key -> CommandCleanup
 cleanup k = do
-	l <- map unwrapmeta . fromMetaData <$> getCurrentMetaData k
-	maybeShowJSON (JSONObject l)
-	showLongNote $ unlines $ concatMap showmeta l
+	m <- getCurrentMetaData k
+	let Object o = toJSON (MetaDataFields m)
+	maybeShowJSON $ AesonObject o
+	showLongNote $ unlines $ concatMap showmeta $
+		map unwrapmeta (fromMetaData m)
 	return True
   where
 	unwrapmeta (f, v) = (fromMetaField f, map fromMetaValue (S.toList v))
 	showmeta (f, vs) = map ((f ++ "=") ++) vs
+
+-- Metadata serialized to JSON in the field named "fields" of
+-- a larger object.
+newtype MetaDataFields = MetaDataFields MetaData
+	deriving (Show)
+
+instance ToJSON MetaDataFields where
+	toJSON (MetaDataFields m) = object [ (fieldsField, toJSON m) ]
+
+instance FromJSON MetaDataFields where
+	parseJSON (Object v) = do
+		f <- v .: fieldsField
+		case f of
+			Nothing -> return (MetaDataFields emptyMetaData)
+			Just v' -> MetaDataFields <$> parseJSON v'
+	parseJSON _ = fail "expected an object"
+
+fieldsField :: T.Text
+fieldsField = T.pack "fields"
+
+parseJSONInput :: String -> Maybe (Either FilePath Key, MetaData)
+parseJSONInput i = do
+	v <- decode (BU.fromString i)
+	case parsedAdded v of
+		Nothing -> return (parsedKeyfile v, emptyMetaData)
+		Just (MetaDataFields m) -> return (parsedKeyfile v, m)
diff --git a/Types/MetaData.hs b/Types/MetaData.hs
index 449548d53e..a62dd7ed08 100644
--- a/Types/MetaData.hs
+++ b/Types/MetaData.hs
@@ -44,14 +44,32 @@ import Common
 import Utility.Base64
 import Utility.QuickCheck
 
+import qualified Data.Text as T
 import qualified Data.Set as S
 import qualified Data.Map as M
+import qualified Data.HashMap.Strict as HM
 import Data.Char
 import qualified Data.CaseInsensitive as CI
+import Data.Aeson
 
 newtype MetaData = MetaData (M.Map MetaField (S.Set MetaValue))
 	deriving (Show, Eq, Ord)
 
+instance ToJSON MetaData where
+	toJSON (MetaData m) = object $ map go (M.toList m)
+	  where
+		go (MetaField f, s) = (T.pack (CI.original f), toJSON s)
+
+instance FromJSON MetaData where
+	parseJSON (Object o) = do
+		l <- HM.toList <$> parseJSON (Object o)
+		MetaData . M.fromList <$> mapM go l
+	  where
+		go (t, l) = case mkMetaField (T.unpack t) of
+			Left e -> fail e
+			Right f -> (,) <$> pure f <*> parseJSON l
+	parseJSON _ = fail "expected an object"
+
 {- A metadata value can be currently be set (True), or may have been
  - set before and we're remembering it no longer is (False). -}
 newtype CurrentlySet = CurrentlySet Bool
@@ -64,6 +82,13 @@ newtype MetaField = MetaField (CI.CI String)
 data MetaValue = MetaValue CurrentlySet String
 	deriving (Read, Show)
 
+instance ToJSON MetaValue where
+	toJSON (MetaValue _ v) = toJSON v
+
+instance FromJSON MetaValue where
+	parseJSON (String v) = return $ MetaValue (CurrentlySet True) (T.unpack v)
+	parseJSON _  = fail "expected a string"
+
 {- Metadata values compare and order the same whether currently set or not. -}
 instance Eq MetaValue where
 	MetaValue _ a == MetaValue _ b = a == b
diff --git a/debian/control b/debian/control
index f9dfec92e9..30c4274ce9 100644
--- a/debian/control
+++ b/debian/control
@@ -25,6 +25,7 @@ Build-Depends:
 	libghc-uuid-dev,
 	libghc-json-dev,
 	libghc-aeson-dev,
+	libghc-unordered-containers-dev,
 	libghc-ifelse-dev,
 	libghc-bloomfilter-dev,
 	libghc-edit-distance-dev,
diff --git a/doc/git-annex-metadata.mdwn b/doc/git-annex-metadata.mdwn
index fe344ff5e5..b4e7900808 100644
--- a/doc/git-annex-metadata.mdwn
+++ b/doc/git-annex-metadata.mdwn
@@ -71,6 +71,16 @@ When run without any -s or -t parameters, displays the current metadata.
   Enable JSON output. This is intended to be parsed by programs that use
   git-annex. Each line of output is a JSON object.
 
+  The format of the JSON objects changed in git-annex version 6.20160726.
+
+  Example of the new format:
+
+	{"command":"metadata","file":"foo","key":"...","fields":{"author":["bar"],...},"note":"...","success":true}
+
+  Example of the old format, which lacks the inner fields object:
+
+	{"command":"metadata","file":"foo","key":"...","author":["bar"],...,"note":"...","success":true}
+
 * `--all`
 
   Specify instead of a file to get/set metadata on all known keys.
diff --git a/git-annex.cabal b/git-annex.cabal
index d0ee988492..f9033cc389 100644
--- a/git-annex.cabal
+++ b/git-annex.cabal
@@ -323,7 +323,7 @@ Executable git-annex
   Build-Depends:
    base (>= 4.5 && < 5.0),
    optparse-applicative (>= 0.11.0), 
-   containers (>= 0.5.0.0), 
+   containers (>= 0.5.0.0),
    exceptions (>= 0.6),
    QuickCheck (>= 2.1),
    stm (>= 2.3),
@@ -338,6 +338,7 @@ Executable git-annex
    time, old-locale,
    esqueleto, persistent-sqlite, persistent (<2.5), persistent-template,
    aeson,
+   unordered-containers,
    feed,
    regex-tdfa
   CC-Options: -Wall