diff --git a/dialogue-pdu.go b/dialogue-pdu.go
index 7872860..4c097f8 100644
--- a/dialogue-pdu.go
+++ b/dialogue-pdu.go
@@ -7,8 +7,6 @@ package tcap
 import (
 	"fmt"
 	"io"
-
-	"github.com/pkg/errors"
 )
 
 // Code definitions.
@@ -266,11 +264,11 @@ func NewAUDT(protover int, context, contextver uint8, userinfo ...*IE) *Dialogue
 }
 */
 
-// MarshalBinary returns the byte sequence generated from a Dialogue instance.
+// MarshalBinary returns the byte sequence generated from a DialoguePDU.
 func (d *DialoguePDU) MarshalBinary() ([]byte, error) {
 	b := make([]byte, d.MarshalLen())
 	if err := d.MarshalTo(b); err != nil {
-		return nil, errors.Wrap(err, "failed to marshal DialoguePDU:")
+		return nil, fmt.Errorf("failed to marshal DialoguePDU: %w", err)
 	}
 	return b, nil
 }
diff --git a/dialogue.go b/dialogue.go
index 609df5d..0af0967 100644
--- a/dialogue.go
+++ b/dialogue.go
@@ -7,8 +7,6 @@ package tcap
 import (
 	"fmt"
 	"io"
-
-	"github.com/pkg/errors"
 )
 
 // Dialogue OID: Dialogue-As-ID and Unidialogue-As-Id.
@@ -51,11 +49,11 @@ func NewDialogue(oid, ver uint8, pdu *DialoguePDU, payload []byte) *Dialogue {
 	return d
 }
 
-// MarshalBinary returns the byte sequence generated from a Dialogue instance.
+// MarshalBinary returns the byte sequence generated from a Dialogue.
 func (d *Dialogue) MarshalBinary() ([]byte, error) {
 	b := make([]byte, d.MarshalLen())
 	if err := d.MarshalTo(b); err != nil {
-		return nil, errors.Wrap(err, "failed to serialize Dialogue:")
+		return nil, fmt.Errorf("failed to marshal Dialogue: %w", err)
 	}
 	return b, nil
 }
diff --git a/go.mod b/go.mod
index 2caed61..df130e9 100644
--- a/go.mod
+++ b/go.mod
@@ -5,9 +5,11 @@ go 1.21
 require (
 	github.com/ishidawataru/sctp v0.0.0-20191218070446-00ab2ac2db07
 	github.com/pascaldekloe/goe v0.1.1
-	github.com/pkg/errors v0.9.1
 	github.com/wmnsk/go-m3ua v0.1.8
 	github.com/wmnsk/go-sccp v0.0.1
 )
 
-require github.com/google/go-cmp v0.5.4 // indirect
+require (
+	github.com/google/go-cmp v0.5.4 // indirect
+	github.com/pkg/errors v0.9.1 // indirect
+)