diff --git a/CHANGES.md b/CHANGES.md
index 05ca6d9..2c67149 100644
--- a/CHANGES.md
+++ b/CHANGES.md
@@ -1,3 +1,8 @@
+## Version 4.0.1 (2026/08/17)
+
+* **Added**
+  * Added configure option for pip install without build isolation (`--without-build-isolation`).
+
 ## Version 4.0.0 (2026/05/30)
 
 * **Changed**
diff --git a/configure.ac b/configure.ac
index a88d08e..57ddedb 100644
--- a/configure.ac
+++ b/configure.ac
@@ -9,7 +9,7 @@ dnl See https://mit-license.org/ and LICENSE.md and for license information.
 dnl ================================================================================================
 
 AC_PREREQ(2.59)
-AC_INIT([spatialdata], [4.0.0], [baagaard@usgs.gov])
+AC_INIT([spatialdata], [4.0.1], [baagaard@usgs.gov])
 AC_CONFIG_HEADER([portinfo])
 AC_CONFIG_AUX_DIR([./aux-config])
 AC_CONFIG_MACRO_DIR([m4])
diff --git a/docs/conf.py b/docs/conf.py
index 5db1dce..13af5f9 100644
--- a/docs/conf.py
+++ b/docs/conf.py
@@ -22,7 +22,7 @@
 author = "Brad T. Aagaard"
 
 # The full version, including alpha/beta/rc tags
-release = "4.0.0"
+release = "4.0.1"
 
 
 # -- General configuration ---------------------------------------------------
diff --git a/setup.cfg b/setup.cfg
index 91a6d3c..7f5f87c 100644
--- a/setup.cfg
+++ b/setup.cfg
@@ -4,7 +4,7 @@ tag_date = 0
 
 [metadata]
 name = spatialdata
-version = 4.0.0
+version = 4.0.1
 author = Brad Aagaard
 author_email = baagaard@usgs.gov
 description = Library for specifying spatial variations in input parameters (used in PyLith).