diff --git a/psycopg/connection.h b/psycopg/connection.h
index 979b37fd..a5aa267a 100644
--- a/psycopg/connection.h
+++ b/psycopg/connection.h
@@ -119,6 +119,8 @@ typedef struct {
     int equote;               /* use E''-style quotes for escaped strings */
     PyObject *weakreflist;    /* list of weak references */
 
+    int autocommit;
+
 } connectionObject;
 
 /* C-callable functions in connection_int.c and connection_ext.c */
diff --git a/psycopg/connection_int.c b/psycopg/connection_int.c
index b0ed41df..5e2ba023 100644
--- a/psycopg/connection_int.c
+++ b/psycopg/connection_int.c
@@ -989,7 +989,8 @@ conn_set(connectionObject *self, const char *param, const char *value)
 int
 conn_set_autocommit(connectionObject *self, int value)
 {
-    return -1;
+    self->autocommit = value;
+    return 0;
 }
 
 /* conn_switch_isolation_level - switch isolation level on the connection */
diff --git a/psycopg/connection_type.c b/psycopg/connection_type.c
index 299888a1..33a69555 100644
--- a/psycopg/connection_type.c
+++ b/psycopg/connection_type.c
@@ -517,6 +517,42 @@ psyco_conn_set_transaction(connectionObject *self, PyObject *args, PyObject *kwa
 }
 
 
+#define psyco_conn_autocommit_doc \
+"set or return the autocommit status."
+
+static PyObject *
+psyco_conn_autocommit_get(connectionObject *self)
+{
+    PyObject *ret;
+    ret = self->autocommit ? Py_True : Py_False;
+    Py_INCREF(ret);
+    return ret;
+}
+
+static PyObject *
+_psyco_conn_autocommit_set_checks(connectionObject *self)
+{
+    /* wrapper to use the EXC_IF macros.
+     * return NULL in case of error, else whatever */
+    EXC_IF_CONN_CLOSED(self);
+    EXC_IF_CONN_ASYNC(self, autocommit);
+    EXC_IF_IN_TRANSACTION(self, autocommit);
+    return Py_None;     /* borrowed */
+}
+
+static int
+psyco_conn_autocommit_set(connectionObject *self, PyObject *pyvalue)
+{
+    int value;
+
+    if (!_psyco_conn_autocommit_set_checks(self)) { return -1; }
+    if (-1 == (value = PyObject_IsTrue(pyvalue))) { return -1; }
+    if (0 != conn_set_autocommit(self, value)) { return -1; }
+
+    return 0;
+}
+
+
 /* set_isolation_level method - switch connection isolation level */
 
 #define psyco_conn_set_isolation_level_doc \
@@ -927,6 +963,12 @@ static struct PyGetSetDef connectionObject_getsets[] = {
     EXCEPTION_GETTER(IntegrityError),
     EXCEPTION_GETTER(DataError),
     EXCEPTION_GETTER(NotSupportedError),
+#ifdef PSYCOPG_EXTENSIONS
+    { "autocommit",
+        (getter)psyco_conn_autocommit_get,
+        (setter)psyco_conn_autocommit_set,
+        psyco_conn_autocommit_doc },
+#endif
     {NULL}
 };
 #undef EXCEPTION_GETTER
diff --git a/psycopg/pqpath.c b/psycopg/pqpath.c
index a6144229..f945448c 100644
--- a/psycopg/pqpath.c
+++ b/psycopg/pqpath.c
@@ -417,6 +417,11 @@ pq_begin_locked(connectionObject *conn, PGresult **pgres, char **error,
     Dprintf("pq_begin_locked: pgconn = %p, isolevel = %ld, status = %d",
             conn->pgconn, conn->isolation_level, conn->status);
 
+    if (conn->autocommit) {
+        Dprintf("pq_begin_locked: autocommit");
+        return 0;
+    }
+
     if (conn->isolation_level == ISOLATION_LEVEL_AUTOCOMMIT
             || conn->status != CONN_STATUS_READY) {
         Dprintf("pq_begin_locked: transaction in progress");
diff --git a/tests/test_connection.py b/tests/test_connection.py
index 18c9277e..90014574 100755
--- a/tests/test_connection.py
+++ b/tests/test_connection.py
@@ -851,6 +851,98 @@ class TransactionControlTests(unittest.TestCase):
             self.conn.set_transaction, readonly=True, deferrable=True)
 
 
+class AutocommitTests(unittest.TestCase):
+    def setUp(self):
+        self.conn = psycopg2.connect(dsn)
+
+    def tearDown(self):
+        if not self.conn.closed:
+            self.conn.close()
+
+    def test_default_no_autocommit(self):
+        self.assert_(not self.conn.autocommit)
+        self.assertEqual(self.conn.status, psycopg2.extensions.STATUS_READY)
+        self.assertEqual(self.conn.get_transaction_status(),
+            psycopg2.extensions.TRANSACTION_STATUS_IDLE)
+
+        cur = self.conn.cursor()
+        cur.execute('select 1;')
+        self.assertEqual(self.conn.status, psycopg2.extensions.STATUS_BEGIN)
+        self.assertEqual(self.conn.get_transaction_status(),
+            psycopg2.extensions.TRANSACTION_STATUS_INTRANS)
+
+        self.conn.rollback()
+        self.assertEqual(self.conn.status, psycopg2.extensions.STATUS_READY)
+        self.assertEqual(self.conn.get_transaction_status(),
+            psycopg2.extensions.TRANSACTION_STATUS_IDLE)
+
+    def test_set_autocommit(self):
+        self.conn.autocommit = True
+        self.assert_(self.conn.autocommit)
+        self.assertEqual(self.conn.status, psycopg2.extensions.STATUS_READY)
+        self.assertEqual(self.conn.get_transaction_status(),
+            psycopg2.extensions.TRANSACTION_STATUS_IDLE)
+
+        cur = self.conn.cursor()
+        cur.execute('select 1;')
+        self.assertEqual(self.conn.status, psycopg2.extensions.STATUS_READY)
+        self.assertEqual(self.conn.get_transaction_status(),
+            psycopg2.extensions.TRANSACTION_STATUS_IDLE)
+
+        self.conn.autocommit = False
+        self.assert_(not self.conn.autocommit)
+        self.assertEqual(self.conn.status, psycopg2.extensions.STATUS_READY)
+        self.assertEqual(self.conn.get_transaction_status(),
+            psycopg2.extensions.TRANSACTION_STATUS_IDLE)
+
+        cur.execute('select 1;')
+        self.assertEqual(self.conn.status, psycopg2.extensions.STATUS_BEGIN)
+        self.assertEqual(self.conn.get_transaction_status(),
+            psycopg2.extensions.TRANSACTION_STATUS_INTRANS)
+
+    def test_set_intrans_error(self):
+        cur = self.conn.cursor()
+        cur.execute('select 1;')
+        self.assertRaises(psycopg2.ProgrammingError,
+            setattr, self.conn, 'autocommit', True)
+
+    def test_set_transaction_autocommit(self):
+        self.conn.set_transaction(autocommit=True)
+        self.assert_(self.conn.autocommit)
+        self.assertEqual(self.conn.status, psycopg2.extensions.STATUS_READY)
+        self.assertEqual(self.conn.get_transaction_status(),
+            psycopg2.extensions.TRANSACTION_STATUS_IDLE)
+
+        cur = self.conn.cursor()
+        cur.execute('select 1;')
+        self.assertEqual(self.conn.status, psycopg2.extensions.STATUS_READY)
+        self.assertEqual(self.conn.get_transaction_status(),
+            psycopg2.extensions.TRANSACTION_STATUS_IDLE)
+
+        self.conn.set_transaction(autocommit=False)
+        self.assert_(not self.conn.autocommit)
+        self.assertEqual(self.conn.status, psycopg2.extensions.STATUS_READY)
+        self.assertEqual(self.conn.get_transaction_status(),
+            psycopg2.extensions.TRANSACTION_STATUS_IDLE)
+
+        cur.execute('select 1;')
+        self.assertEqual(self.conn.status, psycopg2.extensions.STATUS_BEGIN)
+        self.assertEqual(self.conn.get_transaction_status(),
+            psycopg2.extensions.TRANSACTION_STATUS_INTRANS)
+        self.conn.rollback()
+
+        self.conn.set_transaction('serializable', readonly=True, autocommit=True)
+        self.assert_(self.conn.autocommit)
+        cur.execute('select 1;')
+        self.assertEqual(self.conn.status, psycopg2.extensions.STATUS_READY)
+        self.assertEqual(self.conn.get_transaction_status(),
+            psycopg2.extensions.TRANSACTION_STATUS_IDLE)
+        cur.execute("SHOW default_transaction_isolation;")
+        self.assertEqual(cur.fetchone()[0], 'serializable')
+        cur.execute("SHOW default_transaction_read_only;")
+        self.assertEqual(cur.fetchone()[0], 'on')
+
+
 def test_suite():
     return unittest.TestLoader().loadTestsFromName(__name__)