diff --git a/buildtools/version.py b/buildtools/version.py
index 2a01c213..cac84314 100644
--- a/buildtools/version.py
+++ b/buildtools/version.py
@@ -2,7 +2,7 @@
 # Name:        buildtools.version
 # Purpose:     wxPython project name and version numbers used in the
 #              build.  This can be considered the master copy of the
-#              version digits.
+#              version digits and project name.
 #
 # Author:      Robin Dunn
 #
@@ -11,12 +11,20 @@
 # License:     wxWindows License
 #----------------------------------------------------------------------
 
-PROJECT_NAME     = 'wxPython_Phoenix'
+# Master copy of the project name
+PROJECT_NAME     = 'wxPython'
 
-VER_MAJOR        = 3      # Matches wxWidgets MAJOR version number
-VER_MINOR        = 0      # Matches wxWidgets MINOR version number
-VER_RELEASE      = 4      # wxPython RELEASE number for the given wxWidgets
-                          # MAJOR.MINOR version.
+
+# The version numbers for wxPython are no longer kept in sync with the
+# wxWidgets version number. In the past the common version number was used to
+# indicate which version of wxWidgets should be used for the wxPython build.
+# Now wxWidgets is a git submodule, and the linked version is included in the
+# wxPython source tarball. That said, we should still bump up the MAJOR and
+# MINOR numbers each time there is a corresponding bump in the wxWidgets
+# version numbers.
+VER_MAJOR        = 4
+VER_MINOR        = 0
+VER_RELEASE      = 0
 
 VER_FLAGS        = "a1"     # wxPython release flags
 
diff --git a/demo/version.py b/demo/version.py
index af8d65bf..c274123d 100644
--- a/demo/version.py
+++ b/demo/version.py
@@ -1,3 +1,3 @@
 # This file was generated by Phoenix's wscript.
 
-VERSION_STRING = '3.0.4a1'
+VERSION_STRING = '4.0.0a1'
diff --git a/docs/MigrationGuide.rst b/docs/MigrationGuide.rst
index e1aa3fb5..0c2bf7f5 100644
--- a/docs/MigrationGuide.rst
+++ b/docs/MigrationGuide.rst
@@ -22,21 +22,20 @@ should then be able to work out the details for themselves.
 Version Numbers
 ---------------
 
-Classic wxPython used version numbers with 4 components, in order to be able
-to specify the exact version of wxWidgets used (3 version number components)
-and an additional component to allow for multiple wxPython releases for each
-wxWidgets release. While this version numbering works okay and solves a
-specific need that wxPython had, it does not follow the common version
-numbering pattern that probably 99% of other software packages use and so it
-is non-intuitive for most users.
+The version numbers for wxPython are no longer kept in sync with the wxWidgets
+version number. In the past the common version number was used to indicate
+exactly which version of wxWidgets should be used for the wxPython build. Now
+wxWidgets is a git submodule, and the linked version is included in the
+wxPython source tarball there is no longer any need to use the matching
+version numbers to implicitly specify the version of the wxWidgets source to
+use.
 
-So Phoenix will be moving to a 3 component version number, where the first 2
-components match the MAJOR.MINOR version of wxWidgets being used, and the 3rd
-component of the version number is used to indicate the release of wxPython
-Phoenix using that version of wxWidgets.  It is felt that matching the 3rd
-component of the wxWidgets is no longer as important as it was in the past,
-because the wxWidgets source is being included with the Phoenix source, so
-matching exact versions of the two packages by hand is no longer needed.
+This means that wxPython can go back to a 3-component version number and follow
+the common conventions used by 99% of the other software projects out there.
+The 3 components are commonly called MAJOR, MINOR and RELEASE. Since wxPython
+Phoenix is a major upgrade over wxPython Classic then we will start out with a
+new MAJOR version number to help communicate that this isn't just a little
+update from previous releases.
 
 Additional flags will be appended to the version number in a manner that is
 compliant with Python's PEP-440_. This includes syntax for alpha, beta,
diff --git a/src/core_ex.py b/src/core_ex.py
index 9d1f09a5..494c9dfe 100644
--- a/src/core_ex.py
+++ b/src/core_ex.py
@@ -1,13 +1,10 @@
 import sys as _sys
 
-# Load version numbers from __version__...  Ensure that major and minor
-# versions are the same for both wxPython and wxWidgets.
+# Load version numbers from __version__ and some other initialization tasks...
 if 'wxEVT_NULL' in dir():
     from wx.__version__ import *
     import wx._core
     __version__ = VERSION_STRING
-    assert MAJOR_VERSION == wx._core.MAJOR_VERSION, "wxPython/wxWidgets version mismatch"
-    assert MINOR_VERSION == wx._core.MINOR_VERSION, "wxPython/wxWidgets version mismatch"
 
     # Register a function to be called when Python terminates that will clean
     # up and release all system resources that wxWidgets allocated.