diff --git a/clang/docs/ReleaseNotes.rst b/clang/docs/ReleaseNotes.rst
index 005bf99a62457..94e0f10a31743 100644
--- a/clang/docs/ReleaseNotes.rst
+++ b/clang/docs/ReleaseNotes.rst
@@ -368,6 +368,14 @@ libclang
   has an evaluable bit width. Fixes undefined behavior when called on a
   bit-field whose width depends on a template paramter.
 
+- ``clang_parseTranslationUnit`` and ``clang_parseTranslationUnit2`` have been
+  changed to automatically locate the Clang installation directory relative to
+  the location of the libclang binary and use it for system headers installed
+  alongside the Clang installation. It is no longer necessary to manually
+  locate such system headers or use the ``clang_parseTranslationUnit2FullArgv``
+  function for this purpose if libclang has been installed in the default
+  location.
+ 
 Static Analyzer
 ---------------
 - Fix incorrect alignment attribute on the this parameter of certain
diff --git a/clang/include/clang-c/Index.h b/clang/include/clang-c/Index.h
index c7d32e6a152ae..8275f2941a41c 100644
--- a/clang/include/clang-c/Index.h
+++ b/clang/include/clang-c/Index.h
@@ -899,8 +899,13 @@ CINDEX_LINKAGE enum CXErrorCode clang_parseTranslationUnit2(
 
 /**
  * Same as clang_parseTranslationUnit2 but requires a full command line
- * for \c command_line_args including argv[0]. This is useful if the standard
- * library paths are relative to the binary.
+ * for \c command_line_args including argv[0].
+ *
+ * This is useful if the driver uses paths relative to the binary and either
+ * you are targeting libclang versions older than Clang 17, or libclang is
+ * installed to a non-standard location. Clang 17 and newer will automatically
+ * use the correct argv[0] if libclang is installed in the lib directory
+ * parallel to the bin directory where the clang binary is installed.
  */
 CINDEX_LINKAGE enum CXErrorCode clang_parseTranslationUnit2FullArgv(
     CXIndex CIdx, const char *source_filename,
diff --git a/clang/test/Index/record-completion-invocation.c b/clang/test/Index/record-completion-invocation.c
index 4b667134fa2d4..75eb9083908ae 100644
--- a/clang/test/Index/record-completion-invocation.c
+++ b/clang/test/Index/record-completion-invocation.c
@@ -9,4 +9,4 @@
 // RUN: env LIBCLANG_DISABLE_CRASH_RECOVERY=1 CINDEXTEST_INVOCATION_EMISSION_PATH=%t not --crash c-index-test -code-completion-at=%s:10:1 "-remap-file=%s,%S/Inputs/record-parsing-invocation-remap.c" %s
 // RUN: cat %t/libclang-* | FileCheck %s
 
-// CHECK: {"toolchain":"{{.*}}","libclang.operation":"complete","libclang.opts":1,"args":["clang","-fno-spell-checking","{{.*}}record-completion-invocation.c","-Xclang","-detailed-preprocessing-record","-fallow-editor-placeholders"],"invocation-args":["-code-completion-at={{.*}}record-completion-invocation.c:10:1"],"unsaved_file_hashes":[{"name":"{{.*}}record-completion-invocation.c","md5":"aee23773de90e665992b48209351d70e"}]}
+// CHECK: {"toolchain":"{{.*}}","libclang.operation":"complete","libclang.opts":1,"args":["{{.*}}bin{{.*}}clang","-fno-spell-checking","{{.*}}record-completion-invocation.c","-Xclang","-detailed-preprocessing-record","-fallow-editor-placeholders"],"invocation-args":["-code-completion-at={{.*}}record-completion-invocation.c:10:1"],"unsaved_file_hashes":[{"name":"{{.*}}record-completion-invocation.c","md5":"aee23773de90e665992b48209351d70e"}]}
diff --git a/clang/test/Index/record-parsing-invocation.c b/clang/test/Index/record-parsing-invocation.c
index e0c4cdb05fb00..f370f014fb1cc 100644
--- a/clang/test/Index/record-parsing-invocation.c
+++ b/clang/test/Index/record-parsing-invocation.c
@@ -25,5 +25,5 @@
 #  pragma clang __debug parser_crash
 #endif
 
-// CHECK: {"toolchain":"{{.*}}","libclang.operation":"parse","libclang.opts":1,"args":["clang","-fno-spell-checking","{{.*}}record-parsing-invocation.c","-Xclang","-detailed-preprocessing-record","-fallow-editor-placeholders"]}
-// CHECK-UNSAVED: {"toolchain":"{{.*}}","libclang.operation":"parse","libclang.opts":1,"args":["clang","-fno-spell-checking","{{.*}}record-parsing-invocation.c","-Xclang","-detailed-preprocessing-record","-fallow-editor-placeholders"],"unsaved_file_hashes":[{"name":"{{.*}}record-parsing-invocation.c","md5":"aee23773de90e665992b48209351d70e"}]}
+// CHECK: {"toolchain":"{{.*}}","libclang.operation":"parse","libclang.opts":1,"args":["{{.*}}bin{{.*}}clang","-fno-spell-checking","{{.*}}record-parsing-invocation.c","-Xclang","-detailed-preprocessing-record","-fallow-editor-placeholders"]}
+// CHECK-UNSAVED: {"toolchain":"{{.*}}","libclang.operation":"parse","libclang.opts":1,"args":["{{.*}}bin{{.*}}clang","-fno-spell-checking","{{.*}}record-parsing-invocation.c","-Xclang","-detailed-preprocessing-record","-fallow-editor-placeholders"],"unsaved_file_hashes":[{"name":"{{.*}}record-parsing-invocation.c","md5":"aee23773de90e665992b48209351d70e"}]}
diff --git a/clang/tools/libclang/CIndex.cpp b/clang/tools/libclang/CIndex.cpp
index 30416e46ce173..2aa12667d37e9 100644
--- a/clang/tools/libclang/CIndex.cpp
+++ b/clang/tools/libclang/CIndex.cpp
@@ -4013,8 +4013,17 @@ enum CXErrorCode clang_parseTranslationUnit2(
     struct CXUnsavedFile *unsaved_files, unsigned num_unsaved_files,
     unsigned options, CXTranslationUnit *out_TU) {
   noteBottomOfStack();
+
+  if (!CIdx)
+    return CXError_InvalidArguments;
+
+  SmallString<64> ClangPath(
+      static_cast<CIndexer *>(CIdx)->getClangToolchainPath());
+  llvm::sys::path::append(ClangPath, "bin");
+  llvm::sys::path::append(ClangPath, "clang");
+
   SmallVector<const char *, 4> Args;
-  Args.push_back("clang");
+  Args.push_back(ClangPath.c_str());
   Args.append(command_line_args, command_line_args + num_command_line_args);
   return clang_parseTranslationUnit2FullArgv(
       CIdx, source_filename, Args.data(), Args.size(), unsaved_files,