diff --git a/hugolib/site.go b/hugolib/site.go
index d72b29795..a91eefcbc 100644
--- a/hugolib/site.go
+++ b/hugolib/site.go
@@ -114,7 +114,7 @@ type SiteInfo struct {
 	BuildDrafts         bool
 	canonifyUrls        bool
 	paginationPageCount uint64
-	Data            *map[string]interface{}
+	Data                *map[string]interface{}
 }
 
 // SiteSocial is a place to put social details on a site level. These are the
@@ -269,12 +269,12 @@ func (s *Site) addTemplate(name, data string) error {
 
 func (s *Site) loadData(fs source.Input) (err error) {
 	s.Data = make(map[string]interface{})
+	var current map[string]interface{}
 
 	for _, r := range fs.Files() {
 		// Crawl in data tree to insert data
-		var current map[string]interface{}
 		current = s.Data
-		for _, key := range strings.Split(r.Dir(), string(os.PathSeparator)) {
+		for _, key := range strings.Split(r.Dir(), helpers.FilePathSeparator) {
 			if key != "" {
 				if _, ok := current[key]; !ok {
 					current[key] = make(map[string]interface{})
@@ -283,8 +283,7 @@ func (s *Site) loadData(fs source.Input) (err error) {
 			}
 		}
 
-		// Read data file
-		data, err := readFile(r)
+		data, err := readData(r)
 		if err != nil {
 			return err
 		}
@@ -295,10 +294,10 @@ func (s *Site) loadData(fs source.Input) (err error) {
 
 			for key, value := range current[r.BaseFileName()].(map[string]interface{}) {
 				if _, override := data[key]; override {
-					return errors.New("Data in " + r.Path() + " is overrided in subfolder.")
-				} else {
-					data[key] = value
+					// filepath.Walk walks the files in lexical order, '/' comes before '.'
+					jww.ERROR.Printf("Data for key '%s' in path '%s' is overridden in subfolder", key, r.Path())
 				}
+				data[key] = value
 			}
 		}
 
@@ -309,7 +308,7 @@ func (s *Site) loadData(fs source.Input) (err error) {
 	return
 }
 
-func readFile(f *source.File) (interface{}, error) {
+func readData(f *source.File) (interface{}, error) {
 	switch f.Extension() {
 	case "yaml", "yml":
 		return parser.HandleYamlMetaData(f.Bytes())
@@ -318,7 +317,7 @@ func readFile(f *source.File) (interface{}, error) {
 	case "toml":
 		return parser.HandleTomlMetaData(f.Bytes())
 	default:
-		return nil, errors.New("Not supported for data: " + f.Extension())
+		return nil, fmt.Errorf("Data not supported for extension '%s'", f.Extension())
 	}
 }
 
@@ -328,11 +327,13 @@ func (s *Site) Process() (err error) {
 	}
 	s.prepTemplates()
 	s.Tmpl.PrintErrors()
+	s.timerStep("initialize & template prep")
+
 	if err = s.loadData(&source.Filesystem{Base: s.absDataDir()}); err != nil {
 		return
 	}
 	s.timerStep("load data")
-	s.timerStep("initialize & template prep")
+
 	if err = s.CreatePages(); err != nil {
 		return
 	}
diff --git a/hugolib/site_test.go b/hugolib/site_test.go
index 145b47558..04af0e61e 100644
--- a/hugolib/site_test.go
+++ b/hugolib/site_test.go
@@ -3,9 +3,9 @@ package hugolib
 import (
 	"bytes"
 	"fmt"
+	"github.com/spf13/hugo/parser"
 	"html/template"
 	"io"
-	"os"
 	"path/filepath"
 	"strings"
 	"testing"
@@ -17,6 +17,7 @@ import (
 	"github.com/spf13/hugo/target"
 	"github.com/spf13/hugo/tpl"
 	"github.com/spf13/viper"
+	"reflect"
 )
 
 const (
@@ -747,17 +748,68 @@ func TestWeightedTaxonomies(t *testing.T) {
 	}
 }
 
-func TestDataDir(t *testing.T) {
+func TestDataDirJson(t *testing.T) {
 	sources := []source.ByteSource{
-		{filepath.FromSlash("test" + string(os.PathSeparator) + "foo.yaml"), []byte("bar: foofoo")},
-		{filepath.FromSlash("test.yaml"), []byte("hello:\n- world: foo")},
+		{filepath.FromSlash("test/foo.json"), []byte(`{ "bar": "foofoo"  }`)},
+		{filepath.FromSlash("test.json"), []byte(`{ "hello": [ { "world": "foo" } ] }`)},
 	}
 
-	s := &Site{}
-	s.loadData(&source.InMemorySource{ByteSource: sources})
+	expected, err := parser.HandleJsonMetaData([]byte(`{ "test": { "hello": [{ "world": "foo"  }] , "foo": { "bar":"foofoo" } } }`))
 
-	expected := "map[test:map[hello:[map[world:foo]] foo:map[bar:foofoo]]]"
-	if fmt.Sprint(s.Data) != expected {
-		t.Errorf("Expected structure '%s', got '%s'", expected, s.Data)
+	if err != nil {
+		t.Fatalf("Error %s", err)
+	}
+
+	doTestDataDir(t, expected, sources)
+}
+
+func TestDataDirToml(t *testing.T) {
+	sources := []source.ByteSource{
+		{filepath.FromSlash("test/kung.toml"), []byte("[foo]\nbar = 1")},
+	}
+
+	expected, err := parser.HandleTomlMetaData([]byte("[test]\n[test.kung]\n[test.kung.foo]\nbar = 1"))
+
+	if err != nil {
+		t.Fatalf("Error %s", err)
+	}
+
+	doTestDataDir(t, expected, sources)
+}
+
+func TestDataDirYamlWithOverridenValue(t *testing.T) {
+	sources := []source.ByteSource{
+		// filepath.Walk walks the files in lexical order, '/' comes before '.'. Simulate this:
+		{filepath.FromSlash("a.yaml"), []byte("a: 1")},
+		{filepath.FromSlash("test/v1.yaml"), []byte("v1-2: 2")},
+		{filepath.FromSlash("test/v2.yaml"), []byte("v2:\n- 2\n- 3")},
+		{filepath.FromSlash("test.yaml"), []byte("v1: 1")},
+	}
+
+	expected := map[string]interface{}{"a": map[string]interface{}{"a": 1},
+		"test": map[string]interface{}{"v1": map[string]interface{}{"v1-2": 2}, "v2": map[string]interface{}{"v2": []interface{}{2, 3}}}}
+
+	doTestDataDir(t, expected, sources)
+}
+
+func TestDataDirUnknownFormat(t *testing.T) {
+	sources := []source.ByteSource{
+		{filepath.FromSlash("test.roml"), []byte("boo")},
+	}
+	s := &Site{}
+	err := s.loadData(&source.InMemorySource{ByteSource: sources})
+	if err == nil {
+		t.Fatalf("Should return an error")
+	}
+}
+
+func doTestDataDir(t *testing.T, expected interface{}, sources []source.ByteSource) {
+	s := &Site{}
+	err := s.loadData(&source.InMemorySource{ByteSource: sources})
+	if err != nil {
+		t.Fatalf("Error loading data: %s", err)
+	}
+	if !reflect.DeepEqual(expected, s.Data) {
+		t.Errorf("Expected structure\n%#v got\n%#v", expected, s.Data)
 	}
 }