diff --git a/.github/workflows/hipobject-documentation-check.yml b/.github/workflows/hipobject-documentation-check.yml
index 722616b6..dd271839 100644
--- a/.github/workflows/hipobject-documentation-check.yml
+++ b/.github/workflows/hipobject-documentation-check.yml
@@ -3,12 +3,10 @@ name: hipObject - Documentation Check
 on:
   pull_request:
     branches: [develop]
-    # docs/conf.py reads the version from the top-level CMakeLists.txt.
     paths: &paths
       - 'docs/**'
       - 'include/**/*.h'
       - 'README.md'
-      - 'CMakeLists.txt'
       - 'cmake/HIPOBJDocumentation.cmake'
       - '.github/workflows/hipobject-documentation-check.yml'
   push:
diff --git a/.github/workflows/hipobject-documentation-deploy.yml b/.github/workflows/hipobject-documentation-deploy.yml
index b88f0720..1cb18043 100644
--- a/.github/workflows/hipobject-documentation-deploy.yml
+++ b/.github/workflows/hipobject-documentation-deploy.yml
@@ -10,11 +10,9 @@ name: hipObject - Documentation Deploy
 on:
   push:
     branches: [develop]
-    # docs/conf.py reads the version from the top-level CMakeLists.txt.
     paths:
       - 'docs/**'
       - 'include/**/*.h'
-      - 'CMakeLists.txt'
       - 'cmake/HIPOBJDocumentation.cmake'
       - '.github/workflows/hipobject-documentation-deploy.yml'
   workflow_dispatch:
diff --git a/AGENTS.md b/AGENTS.md
index c8d404c9..a68b7d5d 100644
--- a/AGENTS.md
+++ b/AGENTS.md
@@ -159,6 +159,10 @@ Notes:
   change what callers can rely on or have to do**, so both need a
   [changelog](#changelog) entry. Fixing a typo or rewording without changing
   the meaning doesn't.
+- **The version is set only in the public header**, by the
+  `HIPOBJ_VERSION_MAJOR`, `HIPOBJ_VERSION_MINOR`, and `HIPOBJ_VERSION_PATCH`
+  macros. The top-level `CMakeLists.txt` and `docs/conf.py` read it from
+  those lines, so keep each one a plain `#define` of a number.
 - **The public header is C**, and C11 and C++11 consumers both have to be able
   to include it. Keep it free of C++-isms and of anything newer than C11 or
   C++11. Every build with `BUILD_TESTING=ON`, including CI's, compiles it as
@@ -758,9 +762,8 @@ Python code must run on **Python 3.10**. Don't use anything newer, such as
   CI:
   [hipobject-documentation-check.yml](.github/workflows/hipobject-documentation-check.yml),
   when the documentation (including `docs/sphinx/requirements.txt`), the
-  public header, `README.md`, the top-level `CMakeLists.txt` (which
-  `docs/conf.py` reads the version from), the documentation's build files,
-  or the workflow file change.
+  public header (which `docs/conf.py` reads the version from), `README.md`,
+  the documentation's build files, or the workflow file change.
 - **The documentation has to build without CMake too.** After the move to
   rocm-systems, Read the Docs will run doxygen in `docs/doxygen` and Sphinx
   on `docs/conf.py` directly, so keep CMake's `@VARIABLE@` substitutions
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 989e8586..4a684ec5 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -7,14 +7,29 @@
 # value, which breaks the download.
 cmake_minimum_required(VERSION 3.25.2)
 
-# The version is here and in the HIPOBJ_VERSION_* macros in
-# include/hipobj.h, and they must match. The hipobj-install test fails if
-# they don't: the installed library reports the header's version, and
-# the test expects this one. It isn't a cache variable, so changing it
-# here takes effect when an existing build directory is reconfigured.
-set(HIPOBJ_VERSION_MAJOR 0)
-set(HIPOBJ_VERSION_MINOR 1)
-set(HIPOBJ_VERSION_PATCH 0)
+# The version is set only in include/hipobj.h, by the HIPOBJ_VERSION_*
+# macros, and read from there. The installed library reports the
+# header's version too, and the hipobj-install test checks that it's
+# this one. docs/conf.py reads the same lines.
+set(HIPOBJ_VERSION_HEADER "${CMAKE_CURRENT_SOURCE_DIR}/include/hipobj.h")
+file(STRINGS "${HIPOBJ_VERSION_HEADER}" HIPOBJ_VERSION_LINES
+  REGEX "^#define[ \t]+HIPOBJ_VERSION_(MAJOR|MINOR|PATCH)[ \t]")
+foreach(part IN ITEMS MAJOR MINOR PATCH)
+  string(REGEX MATCH
+    "#define[ \t]+HIPOBJ_VERSION_${part}[ \t]+([0-9]+)[ \t]*(;|$)"
+    match "${HIPOBJ_VERSION_LINES}")
+  # Not if(NOT CMAKE_MATCH_1): CMake treats a version number of 0 as false
+  if(match STREQUAL "")
+    message(FATAL_ERROR
+      "HIPOBJ_VERSION_${part} isn't defined as a number in "
+      "${HIPOBJ_VERSION_HEADER}")
+  endif()
+  set(HIPOBJ_VERSION_${part} "${CMAKE_MATCH_1}")
+endforeach()
+# Reconfigure when the header changes, so that a new version takes
+# effect without anyone having to rerun CMake
+set_property(DIRECTORY APPEND PROPERTY CMAKE_CONFIGURE_DEPENDS
+  "${HIPOBJ_VERSION_HEADER}")
 set(HIPOBJ_LIBRARY_VERSION
   "${HIPOBJ_VERSION_MAJOR}.${HIPOBJ_VERSION_MINOR}.${HIPOBJ_VERSION_PATCH}")
 
diff --git a/docs/conf.py b/docs/conf.py
index e9052915..4d4dfbd7 100644
--- a/docs/conf.py
+++ b/docs/conf.py
@@ -21,22 +21,29 @@
 # pylint: enable=redefined-builtin
 
 
-def _cmake_version():
-    """Return the version that the top-level CMakeLists.txt sets."""
-    cmake = (Path(__file__).resolve().parent.parent / "CMakeLists.txt").read_text(
-        encoding="utf-8"
-    )
+def _header_version():
+    """Return the version that the HIPOBJ_VERSION_* macros in hipobj.h set."""
+    header = (
+        Path(__file__).resolve().parent.parent / "include" / "hipobj.h"
+    ).read_text(encoding="utf-8")
     parts = []
     for part in ("MAJOR", "MINOR", "PATCH"):
-        match = re.search(rf"^set\(HIPOBJ_VERSION_{part} (\d+)\)$", cmake, re.MULTILINE)
+        match = re.search(
+            rf"^#define[ \t]+HIPOBJ_VERSION_{part}[ \t]+(\d+)[ \t]*$",
+            header,
+            re.MULTILINE,
+        )
         if not match:
-            raise ValueError(f"HIPOBJ_VERSION_{part} not found in CMakeLists.txt")
+            raise ValueError(
+                f"HIPOBJ_VERSION_{part} isn't defined as a number in hipobj.h"
+            )
         parts.append(match.group(1))
     return ".".join(parts)
 
 
-# The project's version, from CMakeLists.txt
-version = _cmake_version()
+# The project's version, from the public header, which is the only
+# place it's set
+version = _header_version()
 release = version
 
 # -- Extensions ----------------------------------------------
diff --git a/include/hipobj.h b/include/hipobj.h
index 27c56d46..9415541b 100644
--- a/include/hipobj.h
+++ b/include/hipobj.h
@@ -103,6 +103,10 @@ extern "C" {
  *  LIBRARY VERSION NUMBERS
  * ------------------------------------------------------- */
 
+/* This is the only place the version is set. CMakeLists.txt and
+ * docs/conf.py read it from these lines, so keep each one in the form
+ * #define HIPOBJ_VERSION_<part> <number>. */
+
 /*! @brief hipObject major version number @ingroup core */
 #define HIPOBJ_VERSION_MAJOR 0
 /*! @brief hipObject minor version number @ingroup core */