diff --git a/sign/sign_test.go b/sign/sign_test.go
index 7b3df89..9032b34 100644
--- a/sign/sign_test.go
+++ b/sign/sign_test.go
@@ -1,15 +1,55 @@
 package sign
 
 import (
-	"testing"
-	"io/ioutil"
+	"crypto/x509"
+	"encoding/pem"
 	"fmt"
+	"io/ioutil"
 	"os"
 	"path/filepath"
+	"testing"
+	"time"
 
 	"bitbucket.org/digitorus/pdf"
+	"bitbucket.org/digitorus/pdfsign/revocation"
 )
 
+const signCertPem = `-----BEGIN CERTIFICATE-----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+-----END CERTIFICATE-----`
+
+const signKeyPem = `-----BEGIN RSA PRIVATE KEY-----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+-----END RSA PRIVATE KEY-----`
+
 func TestReaderCanReadPDF(t *testing.T) {
 	files, err := ioutil.ReadDir("../testfiles")
 	if err != nil {
@@ -54,6 +94,32 @@ func TestSignPDF(t *testing.T) {
 		return
 	}
 
+	certificate_data_block, _ := pem.Decode([]byte(signCertPem))
+	if certificate_data_block == nil {
+		t.Errorf("failed to parse PEM block containing the certificate", err.Error())
+		return
+	}
+
+	cert, err := x509.ParseCertificate(certificate_data_block.Bytes)
+	if err != nil {
+		t.Errorf("%s", err.Error())
+		return
+	}
+
+	key_data_block, _ := pem.Decode([]byte(signKeyPem))
+	if key_data_block == nil {
+		t.Errorf("failed to parse PEM block containing the private key")
+		return
+	}
+
+	pkey, err := x509.ParsePKCS1PrivateKey(key_data_block.Bytes)
+	if err != nil {
+		t.Errorf("%s", err.Error())
+		return
+	}
+
+	certificate_chains := make([][]*x509.Certificate, 0)
+
 	for _, f := range files {
 		ext := filepath.Ext(f.Name())
 		if ext != ".pdf" {
@@ -82,6 +148,37 @@ func TestSignPDF(t *testing.T) {
 			return
 		}
 
-		// @todo: implement signer.
+		err = SignFile("../testfiles/"+f.Name(), "../testfiles/"+f.Name()+".tmp", SignData{
+			Signature: SignDataSignature{
+				Info: SignDataSignatureInfo{
+					Name:        "Jeroen Bobbeldijk",
+					Location:    "Rotterdam",
+					Reason:      "Test",
+					ContactInfo: "Geen",
+					Date:        time.Now().Local(),
+				},
+				CertType: 2,
+				Approval: false,
+			},
+			Signer:            pkey,
+			Certificate:       cert,
+			CertificateChains: certificate_chains,
+			TSA: TSA{
+				URL: "http://aatl-timestamp.globalsign.com/tsa/aohfewat2389535fnasgnlg5m23",
+			},
+			RevocationData:     revocation.InfoArchival{},
+			RevocationFunction: DefaultEmbedRevocationStatusFunction,
+		})
+
+		// Cleanup old files.
+		defer os.Remove("../testfiles/"+f.Name()+".tmp")
+
+		if err != nil {
+			input_file.Close()
+			t.Errorf("%s: %s", f.Name(), err.Error())
+			return
+		}
+
+		input_file.Close()
 	}
-}
\ No newline at end of file
+}