diff --git a/src/encoding/json/example_text_marshaling_test.go b/src/encoding/json/example_text_marshaling_test.go
new file mode 100644
index 0000000000..04c7813b26
--- /dev/null
+++ b/src/encoding/json/example_text_marshaling_test.go
@@ -0,0 +1,67 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package json_test
+
+import (
+	"encoding/json"
+	"fmt"
+	"log"
+	"strings"
+)
+
+type Size int
+
+const (
+	Unrecognized Size = iota
+	Small
+	Large
+)
+
+func (s *Size) UnmarshalText(text []byte) error {
+	switch strings.ToLower(string(text)) {
+	default:
+		*s = Unrecognized
+	case "small":
+		*s = Small
+	case "large":
+		*s = Large
+	}
+	return nil
+}
+
+func (s Size) MarshalText() ([]byte, error) {
+	var name string
+	switch s {
+	default:
+		name = "unrecognized"
+	case Small:
+		name = "small"
+	case Large:
+		name = "large"
+	}
+	return []byte(name), nil
+}
+
+func Example_textMarshalJSON() {
+	blob := `["small","regular","large","unrecognized","small","normal","small","large"]`
+	var inventory []Size
+	if err := json.Unmarshal([]byte(blob), &inventory); err != nil {
+		log.Fatal(err)
+	}
+
+	counts := make(map[Size]int)
+	for _, size := range inventory {
+		counts[size] += 1
+	}
+
+	fmt.Printf("Inventory Counts:\n* Small:        %d\n* Large:        %d\n* Unrecognized: %d\n",
+		counts[Small], counts[Large], counts[Unrecognized])
+
+	// Output:
+	// Inventory Counts:
+	// * Small:        3
+	// * Large:        2
+	// * Unrecognized: 3
+}
diff --git a/src/encoding/xml/example_marshaling_test.go b/src/encoding/xml/example_marshaling_test.go
new file mode 100644
index 0000000000..9f9e801e74
--- /dev/null
+++ b/src/encoding/xml/example_marshaling_test.go
@@ -0,0 +1,84 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package xml_test
+
+import (
+	"encoding/xml"
+	"fmt"
+	"log"
+	"strings"
+)
+
+type Animal int
+
+const (
+	Unknown Animal = iota
+	Gopher
+	Zebra
+)
+
+func (a *Animal) UnmarshalXML(d *xml.Decoder, start xml.StartElement) error {
+	var s string
+	if err := d.DecodeElement(&s, &start); err != nil {
+		return err
+	}
+	switch strings.ToLower(s) {
+	default:
+		*a = Unknown
+	case "gopher":
+		*a = Gopher
+	case "zebra":
+		*a = Zebra
+	}
+
+	return nil
+}
+
+func (a Animal) MarshalXML(e *xml.Encoder, start xml.StartElement) error {
+	var s string
+	switch a {
+	default:
+		s = "unknown"
+	case Gopher:
+		s = "gopher"
+	case Zebra:
+		s = "zebra"
+	}
+	return e.EncodeElement(s, start)
+}
+
+func Example_customMarshalXML() {
+	blob := `
+	<animals>
+		<animal>gopher</animal>
+		<animal>armadillo</animal>
+		<animal>zebra</animal>
+		<animal>unknown</animal>
+		<animal>gopher</animal>
+		<animal>bee</animal>
+		<animal>gopher</animal>
+		<animal>zebra</animal>
+	</animals>`
+	var zoo struct {
+		Animals []Animal `xml:"animal"`
+	}
+	if err := xml.Unmarshal([]byte(blob), &zoo); err != nil {
+		log.Fatal(err)
+	}
+
+	census := make(map[Animal]int)
+	for _, animal := range zoo.Animals {
+		census[animal] += 1
+	}
+
+	fmt.Printf("Zoo Census:\n* Gophers: %d\n* Zebras:  %d\n* Unknown: %d\n",
+		census[Gopher], census[Zebra], census[Unknown])
+
+	// Output:
+	// Zoo Census:
+	// * Gophers: 3
+	// * Zebras:  2
+	// * Unknown: 3
+}
diff --git a/src/encoding/xml/example_text_marshaling_test.go b/src/encoding/xml/example_text_marshaling_test.go
new file mode 100644
index 0000000000..2549cb16ae
--- /dev/null
+++ b/src/encoding/xml/example_text_marshaling_test.go
@@ -0,0 +1,79 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package xml_test
+
+import (
+	"encoding/xml"
+	"fmt"
+	"log"
+	"strings"
+)
+
+type Size int
+
+const (
+	Unrecognized Size = iota
+	Small
+	Large
+)
+
+func (s *Size) UnmarshalText(text []byte) error {
+	switch strings.ToLower(string(text)) {
+	default:
+		*s = Unrecognized
+	case "small":
+		*s = Small
+	case "large":
+		*s = Large
+	}
+	return nil
+}
+
+func (s Size) MarshalText() ([]byte, error) {
+	var name string
+	switch s {
+	default:
+		name = "unrecognized"
+	case Small:
+		name = "small"
+	case Large:
+		name = "large"
+	}
+	return []byte(name), nil
+}
+
+func Example_textMarshalXML() {
+	blob := `
+	<sizes>
+		<size>small</size>
+		<size>regular</size>
+		<size>large</size>
+		<size>unrecognized</size>
+		<size>small</size>
+		<size>normal</size>
+		<size>small</size>
+		<size>large</size>
+	</sizes>`
+	var inventory struct {
+		Sizes []Size `xml:"size"`
+	}
+	if err := xml.Unmarshal([]byte(blob), &inventory); err != nil {
+		log.Fatal(err)
+	}
+
+	counts := make(map[Size]int)
+	for _, size := range inventory.Sizes {
+		counts[size] += 1
+	}
+
+	fmt.Printf("Inventory Counts:\n* Small:        %d\n* Large:        %d\n* Unrecognized: %d\n",
+		counts[Small], counts[Large], counts[Unrecognized])
+
+	// Output:
+	// Inventory Counts:
+	// * Small:        3
+	// * Large:        2
+	// * Unrecognized: 3
+}
diff --git a/src/encoding/xml/marshal.go b/src/encoding/xml/marshal.go
index d393d0610b..add5ece782 100644
--- a/src/encoding/xml/marshal.go
+++ b/src/encoding/xml/marshal.go
@@ -61,6 +61,10 @@ const (
 //       string of length zero.
 //     - an anonymous struct field is handled as if the fields of its
 //       value were part of the outer struct.
+//     - a field implementing Marshaler is written by calling its MarshalXML
+//       method.
+//     - a field implementing encoding.TextMarshaler is written by encoding the
+//       result of its MarshalText method as text.
 //
 // If a field uses a tag "a>b>c", then the element c will be nested inside
 // parent elements a and b. Fields that appear next to each other that name
diff --git a/src/encoding/xml/read.go b/src/encoding/xml/read.go
index 36c7ba6311..12102bc804 100644
--- a/src/encoding/xml/read.go
+++ b/src/encoding/xml/read.go
@@ -92,6 +92,11 @@ import (
 //
 //   * A struct field with tag "-" is never unmarshaled into.
 //
+// If Unmarshal encounters a field type that implements the Unmarshaler
+// interface, Unmarshal calls its UnmarshalXML method to produce the value from
+// the XML element.  Otherwise, if the value implements
+// encoding.TextUnmarshaler, Unmarshal calls that value's UnmarshalText method.
+//
 // Unmarshal maps an XML element to a string or []byte by saving the
 // concatenation of that element's character data in the string or
 // []byte. The saved []byte is never nil.