diff --git a/Lib/importlib/__init__.py b/Lib/importlib/__init__.py
--- a/Lib/importlib/__init__.py
+++ b/Lib/importlib/__init__.py
@@ -46,7 +46,43 @@
             finder.invalidate_caches()
 
 
-def find_spec(name, path=None):
+def _resolve_level(name, package):
+    level = 0
+    if name.startswith('.'):
+        if not package:
+            msg = ("the 'package' argument is required to perform a relative "
+                   "import for {!r}")
+            raise TypeError(msg.format(name))
+        for character in name:
+            if character != '.':
+                break
+            level += 1
+    return name[level:], level
+
+
+# This is an adaptation of importlib._bootstrap._find_and_load_unlocked().
+def _find_unlocked(name):
+    path = None
+    parent = name.rpartition('.')[0]
+    if parent:
+        if parent not in sys.modules:
+            _bootstrap._call_with_frames_removed(_bootstrap._gcd_import,
+                                                 parent)
+        # Crazy side-effects!
+        if name in sys.modules:
+            return None, sys.modules[name]
+        parent_module = sys.modules[parent]
+        try:
+            path = parent_module.__path__
+        except AttributeError:
+            msg = (_bootstrap._ERR_MSG + '; {!r} is not a package'
+                   ).format(name, parent)
+            raise ImportError(msg, name=name)
+    return _bootstrap._find_spec(name, path)
+
+
+# This borrows from importlib._bootstrap._gcd_import().
+def find_spec(name, package=None):
     """Return the spec for the specified module.
 
     First, sys.modules is checked to see if the module was already imported. If
@@ -56,25 +92,36 @@
     value of 'path' given to the finders. None is returned if no spec could
     be found.
 
-    Dotted names do not have their parent packages implicitly imported. You will
-    most likely need to explicitly import all parent packages in the proper
-    order for a submodule to get the correct spec.
+    If the module is a submodule, its parent will be imported as a side
+    effect of finding the spec.  However, the module itself will not be
+    explicitly imported.
+
+    The 'package' argument is required when performing a relative import. It
+    specifies the package to use as the anchor point from which to resolve the
+    relative import to an absolute import.
 
     """
+    name, level = _resolve_level(name, package)
+    _bootstrap._sanity_check(name, package, level)
+    if level > 0:
+        name = _bootstrap._resolve_name(name, package, level)
+    _imp.acquire_lock()
     if name not in sys.modules:
-        return _bootstrap._find_spec(name, path)
+        spec, module = _find_unlocked(name)
+        if module is None:
+            return spec
     else:
         module = sys.modules[name]
         if module is None:
             return None
-        try:
-            spec = module.__spec__
-        except AttributeError:
-            raise ValueError('{}.__spec__ is not set'.format(name))
-        else:
-            if spec is None:
-                raise ValueError('{}.__spec__ is None'.format(name))
-            return spec
+    try:
+        spec = module.__spec__
+    except AttributeError:
+        raise ValueError('{}.__spec__ is not set'.format(name))
+    else:
+        if spec is None:
+            raise ValueError('{}.__spec__ is None'.format(name))
+        return spec
 
 
 # XXX Deprecate...
@@ -116,17 +163,8 @@
     relative import to an absolute import.
 
     """
-    level = 0
-    if name.startswith('.'):
-        if not package:
-            msg = ("the 'package' argument is required to perform a relative "
-                   "import for {!r}")
-            raise TypeError(msg.format(name))
-        for character in name:
-            if character != '.':
-                break
-            level += 1
-    return _bootstrap._gcd_import(name[level:], package, level)
+    name, level = _resolve_level(name, package)
+    return _bootstrap._gcd_import(name, package, level)
 
 
 _RELOADING = {}