diff --git a/docs/x509.rst b/docs/x509.rst
index f79f630..a2a3ded 100644
--- a/docs/x509.rst
+++ b/docs/x509.rst
@@ -473,15 +473,38 @@
 
 .. class:: CertificateSigningRequestBuilder
 
+    .. versionadded:: 1.0
+
+    .. doctest::
+
+        >>> from cryptography import x509
+        >>> from cryptography.hazmat.backends import default_backend
+        >>> from cryptography.hazmat.primitives import hashes
+        >>> from cryptography.hazmat.primitives.asymmetric import rsa
+        >>> private_key = rsa.generate_private_key(
+        ...     public_exponent=65537,
+        ...     key_size=2048,
+        ...     backend=default_backend()
+        ... )
+        >>> builder = x509.CertificateSigningRequestBuilder()
+        >>> builder = builder.set_subject_name(x509.Name([
+        ...     x509.NameAttribute(x509.OID_COMMON_NAME, 'cryptography.io'),
+        ... ]))
+        >>> buidlder = builder.add_extension(x509.Extension(
+        ...     x509.OID_BASIC_CONSTRAINTS,
+        ...     True,
+        ...     x509.BasicConstraints(False, None),
+        ... ))
+        >>> request = builder.sign(
+        ...     default_backend(), private_key, hashes.SHA1()
+        ... )
+        >>> isinstance(request, x509.CertificateSigningRequest)
+        True
+
     .. method:: __init__()
 
         Creates an empty certificate signing request.
 
-    .. method:: set_version(version)
-
-        :param version: The :class:`Version` of the X.509 protocol.
-        :returns: A new `CertificateSigningRequestBuilder`.
-
     .. method:: set_subject_name(name)
 
         :param name: The :class:`Name` of the certificate subject.