diff --git a/src/exec.cpp b/src/exec.cpp
index 6c30797a..5dfe033b 100644
--- a/src/exec.cpp
+++ b/src/exec.cpp
@@ -5,6 +5,7 @@
 
 #include <boost/python/exec.hpp>
 #include <boost/python/borrowed.hpp>
+#include <boost/python/dict.hpp>
 #include <boost/python/extract.hpp>
 #include <boost/python/handle.hpp>
 
@@ -15,6 +16,15 @@ namespace python
 
 object BOOST_PYTHON_DECL eval(str string, object global, object local)
 {
+  // Set suitable default values for global and local dicts.
+  if (!global)
+  {
+    if (PyObject *g = PyEval_GetGlobals())
+      global = object(detail::borrowed_reference(g));
+    else
+      global = dict();
+  }
+  if (!local) local = global;
   // should be 'char const *' but older python versions don't use 'const' yet.
   char *s = python::extract<char *>(string);
   PyObject* result = PyRun_String(s, Py_eval_input, global.ptr(), local.ptr());
@@ -24,6 +34,15 @@ object BOOST_PYTHON_DECL eval(str string, object global, object local)
 
 object BOOST_PYTHON_DECL exec(str string, object global, object local)
 {
+  // Set suitable default values for global and local dicts.
+  if (!global)
+  {
+    if (PyObject *g = PyEval_GetGlobals())
+      global = object(detail::borrowed_reference(g));
+    else
+      global = dict();
+  }
+  if (!local) local = global;
   // should be 'char const *' but older python versions don't use 'const' yet.
   char *s = python::extract<char *>(string);
   PyObject* result = PyRun_String(s, Py_file_input, global.ptr(), local.ptr());
@@ -31,11 +50,38 @@ object BOOST_PYTHON_DECL exec(str string, object global, object local)
   return object(detail::new_reference(result));
 }
 
+object BOOST_PYTHON_DECL exec_statement(str string, object global, object local)
+{
+  // Set suitable default values for global and local dicts.
+  if (!global)
+  {
+    if (PyObject *g = PyEval_GetGlobals())
+      global = object(detail::borrowed_reference(g));
+    else
+      global = dict();
+  }
+  if (!local) local = global;
+  // should be 'char const *' but older python versions don't use 'const' yet.
+  char *s = python::extract<char *>(string);
+  PyObject* result = PyRun_String(s, Py_single_input, global.ptr(), local.ptr());
+  if (!result) throw_error_already_set();
+  return object(detail::new_reference(result));
+}
+
 // Execute python source code from file filename.
 // global and local are the global and local scopes respectively,
 // used during execution.
 object BOOST_PYTHON_DECL exec_file(str filename, object global, object local)
 {
+  // Set suitable default values for global and local dicts.
+  if (!global)
+  {
+    if (PyObject *g = PyEval_GetGlobals())
+      global = object(detail::borrowed_reference(g));
+    else
+      global = dict();
+  }
+  if (!local) local = global;
   // should be 'char const *' but older python versions don't use 'const' yet.
   char *f = python::extract<char *>(filename);
   // Let python open the file to avoid potential binary incompatibilities.