diff --git a/Misc/NEWS b/Misc/NEWS
index 43c55df..60b62b2 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -183,6 +183,9 @@
 Build
 -----
 
+- Issue #9810: Compile bzip2 source files in python's project file
+  directly. It used to be built with bzip2's makefile.
+
 - Issue #9848: Stopping trying to build _weakref in setup.py as it is a
   built-in module.
 
diff --git a/PCbuild/bz2.vcproj b/PCbuild/bz2.vcproj
index 2c16eb0..afda578 100644
--- a/PCbuild/bz2.vcproj
+++ b/PCbuild/bz2.vcproj
@@ -43,6 +43,7 @@
 			<Tool
 				Name="VCCLCompilerTool"
 				AdditionalIncludeDirectories="$(bz2Dir)"
+				PreprocessorDefinitions="WIN32;_FILE_OFFSET_BITS=64"
 			/>
 			<Tool
 				Name="VCManagedResourceCompilerTool"
@@ -52,12 +53,10 @@
 			/>
 			<Tool
 				Name="VCPreLinkEventTool"
-				Description="Build libbz2"
-				CommandLine="cd $(bz2Dir)&#x0D;&#x0A;if exist $(PlatformName)-Debug\libbz2.lib exit 0&#x0D;&#x0A;if not exist $(PlatformName)-Debug mkdir $(PlatformName)-Debug&#x0D;&#x0A;nmake /nologo /f makefile.msc lib&#x0D;&#x0A;copy libbz2.lib $(PlatformName)-Debug&#x0D;&#x0A;nmake /nologo /f makefile.msc clean&#x0D;&#x0A;"
 			/>
 			<Tool
 				Name="VCLinkerTool"
-				AdditionalDependencies="$(bz2Dir)\$(PlatformName)-Debug\libbz2.lib"
+				BaseAddress="0x1D170000"
 			/>
 			<Tool
 				Name="VCALinkTool"
@@ -106,6 +105,7 @@
 			<Tool
 				Name="VCCLCompilerTool"
 				AdditionalIncludeDirectories="$(bz2Dir)"
+				PreprocessorDefinitions="WIN32;_FILE_OFFSET_BITS=64"
 			/>
 			<Tool
 				Name="VCManagedResourceCompilerTool"
@@ -115,12 +115,10 @@
 			/>
 			<Tool
 				Name="VCPreLinkEventTool"
-				Description="Build libbz2"
-				CommandLine="cd $(bz2Dir)&#x0D;&#x0A;if exist $(PlatformName)-Debug\libbz2.lib exit 0&#x0D;&#x0A;if not exist $(PlatformName)-Debug mkdir $(PlatformName)-Debug&#x0D;&#x0A;nmake /nologo /f makefile.msc lib&#x0D;&#x0A;copy libbz2.lib $(PlatformName)-Debug&#x0D;&#x0A;nmake /nologo /f makefile.msc clean&#x0D;&#x0A;"
 			/>
 			<Tool
 				Name="VCLinkerTool"
-				AdditionalDependencies="$(bz2Dir)\$(PlatformName)-Debug\libbz2.lib"
+				BaseAddress="0x1D170000"
 			/>
 			<Tool
 				Name="VCALinkTool"
@@ -169,6 +167,7 @@
 			<Tool
 				Name="VCCLCompilerTool"
 				AdditionalIncludeDirectories="$(bz2Dir)"
+				PreprocessorDefinitions="WIN32;_FILE_OFFSET_BITS=64"
 			/>
 			<Tool
 				Name="VCManagedResourceCompilerTool"
@@ -178,12 +177,10 @@
 			/>
 			<Tool
 				Name="VCPreLinkEventTool"
-				Description="Build libbz2"
-				CommandLine="cd $(bz2Dir)&#x0D;&#x0A;if exist $(PlatformName)-Release\libbz2.lib exit 0&#x0D;&#x0A;if not exist $(PlatformName)-Release mkdir $(PlatformName)-Release&#x0D;&#x0A;nmake /nologo /f makefile.msc lib&#x0D;&#x0A;copy libbz2.lib $(PlatformName)-Release&#x0D;&#x0A;nmake /nologo /f makefile.msc clean&#x0D;&#x0A;"
 			/>
 			<Tool
 				Name="VCLinkerTool"
-				AdditionalDependencies="$(bz2Dir)\$(PlatformName)-Release\libbz2.lib"
+				BaseAddress="0x1D170000"
 			/>
 			<Tool
 				Name="VCALinkTool"
@@ -233,6 +230,7 @@
 			<Tool
 				Name="VCCLCompilerTool"
 				AdditionalIncludeDirectories="$(bz2Dir)"
+				PreprocessorDefinitions="WIN32;_FILE_OFFSET_BITS=64"
 			/>
 			<Tool
 				Name="VCManagedResourceCompilerTool"
@@ -242,12 +240,10 @@
 			/>
 			<Tool
 				Name="VCPreLinkEventTool"
-				Description="Build libbz2"
-				CommandLine="cd $(bz2Dir)&#x0D;&#x0A;if exist $(PlatformName)-Release\libbz2.lib exit 0&#x0D;&#x0A;if not exist $(PlatformName)-Release mkdir $(PlatformName)-Release&#x0D;&#x0A;nmake /nologo /f makefile.msc lib&#x0D;&#x0A;copy libbz2.lib $(PlatformName)-Release&#x0D;&#x0A;nmake /nologo /f makefile.msc clean&#x0D;&#x0A;"
 			/>
 			<Tool
 				Name="VCLinkerTool"
-				AdditionalDependencies="$(bz2Dir)\$(PlatformName)-Release\libbz2.lib"
+				BaseAddress="0x1D170000"
 			/>
 			<Tool
 				Name="VCALinkTool"
@@ -296,6 +292,7 @@
 			<Tool
 				Name="VCCLCompilerTool"
 				AdditionalIncludeDirectories="$(bz2Dir)"
+				PreprocessorDefinitions="WIN32;_FILE_OFFSET_BITS=64"
 			/>
 			<Tool
 				Name="VCManagedResourceCompilerTool"
@@ -305,12 +302,10 @@
 			/>
 			<Tool
 				Name="VCPreLinkEventTool"
-				Description="Build libbz2"
-				CommandLine="cd $(bz2Dir)&#x0D;&#x0A;if exist $(PlatformName)-Release\libbz2.lib exit 0&#x0D;&#x0A;if not exist $(PlatformName)-Release mkdir $(PlatformName)-Release&#x0D;&#x0A;nmake /nologo /f makefile.msc lib&#x0D;&#x0A;copy libbz2.lib $(PlatformName)-Release&#x0D;&#x0A;nmake /nologo /f makefile.msc clean&#x0D;&#x0A;"
 			/>
 			<Tool
 				Name="VCLinkerTool"
-				AdditionalDependencies="$(bz2Dir)\$(PlatformName)-Release\libbz2.lib"
+				BaseAddress="0x1D170000"
 			/>
 			<Tool
 				Name="VCALinkTool"
@@ -360,6 +355,7 @@
 			<Tool
 				Name="VCCLCompilerTool"
 				AdditionalIncludeDirectories="$(bz2Dir)"
+				PreprocessorDefinitions="WIN32;_FILE_OFFSET_BITS=64"
 			/>
 			<Tool
 				Name="VCManagedResourceCompilerTool"
@@ -369,12 +365,10 @@
 			/>
 			<Tool
 				Name="VCPreLinkEventTool"
-				Description="Build libbz2"
-				CommandLine="cd $(bz2Dir)&#x0D;&#x0A;if exist $(PlatformName)-Release\libbz2.lib exit 0&#x0D;&#x0A;if not exist $(PlatformName)-Release mkdir $(PlatformName)-Release&#x0D;&#x0A;nmake /nologo /f makefile.msc lib&#x0D;&#x0A;copy libbz2.lib $(PlatformName)-Release&#x0D;&#x0A;nmake /nologo /f makefile.msc clean&#x0D;&#x0A;"
 			/>
 			<Tool
 				Name="VCLinkerTool"
-				AdditionalDependencies="$(bz2Dir)\$(PlatformName)-Release\libbz2.lib"
+				BaseAddress="0x1D170000"
 				TargetMachine="17"
 			/>
 			<Tool
@@ -424,6 +418,7 @@
 			<Tool
 				Name="VCCLCompilerTool"
 				AdditionalIncludeDirectories="$(bz2Dir)"
+				PreprocessorDefinitions="WIN32;_FILE_OFFSET_BITS=64"
 			/>
 			<Tool
 				Name="VCManagedResourceCompilerTool"
@@ -433,12 +428,10 @@
 			/>
 			<Tool
 				Name="VCPreLinkEventTool"
-				Description="Build libbz2"
-				CommandLine="cd $(bz2Dir)&#x0D;&#x0A;if exist $(PlatformName)-Release\libbz2.lib exit 0&#x0D;&#x0A;if not exist $(PlatformName)-Release mkdir $(PlatformName)-Release&#x0D;&#x0A;nmake /nologo /f makefile.msc lib&#x0D;&#x0A;copy libbz2.lib $(PlatformName)-Release&#x0D;&#x0A;nmake /nologo /f makefile.msc clean&#x0D;&#x0A;"
 			/>
 			<Tool
 				Name="VCLinkerTool"
-				AdditionalDependencies="$(bz2Dir)\$(PlatformName)-Release\libbz2.lib"
+				BaseAddress="0x1D170000"
 			/>
 			<Tool
 				Name="VCALinkTool"
@@ -488,6 +481,7 @@
 			<Tool
 				Name="VCCLCompilerTool"
 				AdditionalIncludeDirectories="$(bz2Dir)"
+				PreprocessorDefinitions="WIN32;_FILE_OFFSET_BITS=64"
 			/>
 			<Tool
 				Name="VCManagedResourceCompilerTool"
@@ -497,12 +491,10 @@
 			/>
 			<Tool
 				Name="VCPreLinkEventTool"
-				Description="Build libbz2"
-				CommandLine="cd $(bz2Dir)&#x0D;&#x0A;if exist $(PlatformName)-Release\libbz2.lib exit 0&#x0D;&#x0A;if not exist $(PlatformName)-Release mkdir $(PlatformName)-Release&#x0D;&#x0A;nmake /nologo /f makefile.msc lib&#x0D;&#x0A;copy libbz2.lib $(PlatformName)-Release&#x0D;&#x0A;nmake /nologo /f makefile.msc clean&#x0D;&#x0A;"
 			/>
 			<Tool
 				Name="VCLinkerTool"
-				AdditionalDependencies="$(bz2Dir)\$(PlatformName)-Release\libbz2.lib"
+				BaseAddress="0x1D170000"
 				TargetMachine="17"
 			/>
 			<Tool
@@ -539,6 +531,50 @@
 				>
 			</File>
 		</Filter>
+		<Filter
+			Name="bzip2 1.0.5 Header Files"
+			>
+			<File
+				RelativePath="$(bz2Dir)\bzlib.h"
+				>
+			</File>
+			<File
+				RelativePath="$(bz2Dir)\bzlib_private.h"
+				>
+			</File>
+		</Filter>
+		<Filter
+			Name="bzip2 1.0.5 Source Files"
+			>
+			<File
+				RelativePath="$(bz2Dir)\blocksort.c"
+				>
+			</File>
+			<File
+				RelativePath="$(bz2Dir)\bzlib.c"
+				>
+			</File>
+			<File
+				RelativePath="$(bz2Dir)\compress.c"
+				>
+			</File>
+			<File
+				RelativePath="$(bz2Dir)\crctable.c"
+				>
+			</File>
+			<File
+				RelativePath="$(bz2Dir)\decompress.c"
+				>
+			</File>
+			<File
+				RelativePath="$(bz2Dir)\huffman.c"
+				>
+			</File>
+			<File
+				RelativePath="$(bz2Dir)\randtable.c"
+				>
+			</File>
+		</Filter>
 	</Files>
 	<Globals>
 	</Globals>