diff --git a/github/github_test.go b/github/github_test.go
index b5c4827..bf4d87e 100644
--- a/github/github_test.go
+++ b/github/github_test.go
@@ -6,6 +6,7 @@
 package github
 
 import (
+	"bytes"
 	"encoding/json"
 	"fmt"
 	"io/ioutil"
@@ -78,6 +79,24 @@ func testURLParseError(t *testing.T, err error) {
 	}
 }
 
+// Helper function to test that a value is marshalled to JSON as expected.
+func testJSONMarshal(t *testing.T, v interface{}, want string) {
+	j, err := json.Marshal(v)
+	if err != nil {
+		t.Errorf("Unable to marshal JSON for %v", v)
+	}
+
+	w := new(bytes.Buffer)
+	err = json.Compact(w, []byte(want))
+	if err != nil {
+		t.Errorf("String is not valid json: %s", want)
+	}
+
+	if w.String() != string(j) {
+		t.Errorf("json.Marshal(%q) returned %s, want %s", v, j, w)
+	}
+}
+
 func TestNewClient(t *testing.T) {
 	c := NewClient(nil)
 
diff --git a/github/users_test.go b/github/users_test.go
index dec8193..f7ff2af 100644
--- a/github/users_test.go
+++ b/github/users_test.go
@@ -13,6 +13,46 @@ import (
 	"testing"
 )
 
+func TestUser_marshall(t *testing.T) {
+	testJSONMarshal(t, &User{}, "{}")
+
+	u := &User{
+		Login:       String("l"),
+		ID:          Int(1),
+		URL:         String("u"),
+		AvatarURL:   String("a"),
+		GravatarID:  String("g"),
+		Name:        String("n"),
+		Company:     String("c"),
+		Blog:        String("b"),
+		Location:    String("l"),
+		Email:       String("e"),
+		Hireable:    Bool(true),
+		PublicRepos: Int(1),
+		Followers:   Int(1),
+		Following:   Int(1),
+		CreatedAt:   &referenceTime,
+	}
+	want := `{
+		"login": "l",
+		"id": 1,
+		"url": "u",
+		"avatar_url": "a",
+		"gravatar_id": "g",
+		"name": "n",
+		"company": "c",
+		"blog": "b",
+		"location": "l",
+		"email": "e",
+		"hireable": true,
+		"public_repos": 1,
+		"followers": 1,
+		"following": 1,
+		"created_at": ` + referenceTimeStr + `
+	}`
+	testJSONMarshal(t, u, want)
+}
+
 func TestUsersService_Get_authenticatedUser(t *testing.T) {
 	setup()
 	defer teardown()