diff --git a/IPhreeqc.2005.vcproj b/IPhreeqc.2005.vcproj
index e78a672f..583906af 100644
--- a/IPhreeqc.2005.vcproj
+++ b/IPhreeqc.2005.vcproj
@@ -1153,6 +1153,22 @@
 				RelativePath=".\src\IPhreeqcLib.cpp"
 				>
 			</File>
+			<File
+				RelativePath=".\src\phreeqcpp\common\Parser.cxx"
+				>
+			</File>
+			<File
+				RelativePath=".\src\phreeqcpp\common\PHRQ_base.cxx"
+				>
+			</File>
+			<File
+				RelativePath=".\src\phreeqcpp\common\PHRQ_io.cpp"
+				>
+			</File>
+			<File
+				RelativePath=".\src\phreeqcpp\common\Utils.cxx"
+				>
+			</File>
 			<File
 				RelativePath=".\src\Var.c"
 				>
@@ -1275,6 +1291,102 @@
 				<File
 					RelativePath=".\src\phreeqcpp\dw.cpp"
 					>
+					<FileConfiguration
+						Name="Release|Win32"
+						ExcludedFromBuild="true"
+						>
+						<Tool
+							Name="VCCLCompilerTool"
+						/>
+					</FileConfiguration>
+					<FileConfiguration
+						Name="Release|x64"
+						ExcludedFromBuild="true"
+						>
+						<Tool
+							Name="VCCLCompilerTool"
+						/>
+					</FileConfiguration>
+					<FileConfiguration
+						Name="Debug|Win32"
+						ExcludedFromBuild="true"
+						>
+						<Tool
+							Name="VCCLCompilerTool"
+						/>
+					</FileConfiguration>
+					<FileConfiguration
+						Name="Debug|x64"
+						ExcludedFromBuild="true"
+						>
+						<Tool
+							Name="VCCLCompilerTool"
+						/>
+					</FileConfiguration>
+					<FileConfiguration
+						Name="ReleaseDll|Win32"
+						ExcludedFromBuild="true"
+						>
+						<Tool
+							Name="VCCLCompilerTool"
+						/>
+					</FileConfiguration>
+					<FileConfiguration
+						Name="ReleaseDll|x64"
+						ExcludedFromBuild="true"
+						>
+						<Tool
+							Name="VCCLCompilerTool"
+						/>
+					</FileConfiguration>
+					<FileConfiguration
+						Name="DebugDll|Win32"
+						ExcludedFromBuild="true"
+						>
+						<Tool
+							Name="VCCLCompilerTool"
+						/>
+					</FileConfiguration>
+					<FileConfiguration
+						Name="DebugDll|x64"
+						ExcludedFromBuild="true"
+						>
+						<Tool
+							Name="VCCLCompilerTool"
+						/>
+					</FileConfiguration>
+					<FileConfiguration
+						Name="DebugCLR|Win32"
+						ExcludedFromBuild="true"
+						>
+						<Tool
+							Name="VCCLCompilerTool"
+						/>
+					</FileConfiguration>
+					<FileConfiguration
+						Name="DebugCLR|x64"
+						ExcludedFromBuild="true"
+						>
+						<Tool
+							Name="VCCLCompilerTool"
+						/>
+					</FileConfiguration>
+					<FileConfiguration
+						Name="ReleaseCLR|Win32"
+						ExcludedFromBuild="true"
+						>
+						<Tool
+							Name="VCCLCompilerTool"
+						/>
+					</FileConfiguration>
+					<FileConfiguration
+						Name="ReleaseCLR|x64"
+						ExcludedFromBuild="true"
+						>
+						<Tool
+							Name="VCCLCompilerTool"
+						/>
+					</FileConfiguration>
 				</File>
 				<File
 					RelativePath=".\src\phreeqcpp\Exchange.cxx"
@@ -1360,10 +1472,6 @@
 					RelativePath=".\src\phreeqcpp\parse.cpp"
 					>
 				</File>
-				<File
-					RelativePath=".\src\phreeqcpp\Parser.cxx"
-					>
-				</File>
 				<File
 					RelativePath=".\src\phreeqcpp\PBasic.cpp"
 					>
@@ -1376,14 +1484,6 @@
 					RelativePath=".\src\phreeqcpp\Phreeqc.cpp"
 					>
 				</File>
-				<File
-					RelativePath=".\src\phreeqcpp\PHRQ_base.cxx"
-					>
-				</File>
-				<File
-					RelativePath=".\src\phreeqcpp\PHRQ_io.cpp"
-					>
-				</File>
 				<File
 					RelativePath=".\src\phreeqcpp\PHRQ_io_output.cpp"
 					>
@@ -1644,10 +1744,6 @@
 					RelativePath=".\src\phreeqcpp\utilities.cpp"
 					>
 				</File>
-				<File
-					RelativePath=".\src\phreeqcpp\Utils.cxx"
-					>
-				</File>
 			</Filter>
 		</Filter>
 		<Filter
@@ -1755,7 +1851,7 @@
 				>
 			</File>
 			<File
-				RelativePath=".\src\phreeqcpp\Keywords.h"
+				RelativePath=".\src\phreeqcpp\PhreeqcKeywords\Keywords.h"
 				>
 			</File>
 			<File
@@ -1783,7 +1879,7 @@
 				>
 			</File>
 			<File
-				RelativePath=".\src\phreeqcpp\Parser.h"
+				RelativePath=".\src\phreeqcpp\common\Parser.h"
 				>
 			</File>
 			<File
@@ -1799,15 +1895,15 @@
 				>
 			</File>
 			<File
-				RelativePath=".\src\phreeqcpp\PHRQ_base.h"
+				RelativePath=".\src\phreeqcpp\common\PHRQ_base.h"
 				>
 			</File>
 			<File
-				RelativePath=".\src\phreeqcpp\PHRQ_io.h"
+				RelativePath=".\src\phreeqcpp\common\PHRQ_io.h"
 				>
 			</File>
 			<File
-				RelativePath=".\src\phreeqcpp\phrqtype.h"
+				RelativePath=".\src\phreeqcpp\common\phrqtype.h"
 				>
 			</File>
 			<File
@@ -1911,7 +2007,7 @@
 				>
 			</File>
 			<File
-				RelativePath=".\src\phreeqcpp\Utils.h"
+				RelativePath=".\src\phreeqcpp\common\Utils.h"
 				>
 			</File>
 			<File
diff --git a/IPhreeqc.vsprops b/IPhreeqc.vsprops
index d277fa76..a666fa47 100644
--- a/IPhreeqc.vsprops
+++ b/IPhreeqc.vsprops
@@ -6,7 +6,7 @@
 	>
 	<Tool
 		Name="VCCLCompilerTool"
-		AdditionalIncludeDirectories="src;src/phreeqcpp;src/phreeqcpp/PhreeqcKeywords"
+		AdditionalIncludeDirectories="src;src/phreeqcpp;src/phreeqcpp/common;src/phreeqcpp/PhreeqcKeywords"
 		PreprocessorDefinitions="SWIG_SHARED_OBJ;PHREEQC_CPP;PHREEQC_CLASS;USE_PHRQ_ALLOC;_CRT_SECURE_NO_DEPRECATE;_SCL_SECURE_NO_WARNINGS"
 	/>
 </VisualStudioPropertySheet>
diff --git a/tests/test_cxx.vcproj b/tests/test_cxx.vcproj
index bdc2db4d..eb520f8d 100644
--- a/tests/test_cxx.vcproj
+++ b/tests/test_cxx.vcproj
@@ -43,7 +43,7 @@
 			<Tool
 				Name="VCCLCompilerTool"
 				Optimization="0"
-				AdditionalIncludeDirectories="../src;../src/phreeqcpp;../src/phreeqcpp/PhreeqcKeywords"
+				AdditionalIncludeDirectories="../src;../src/phreeqcpp;../src/phreeqcpp/common;../src/phreeqcpp/PhreeqcKeywords"
 				PreprocessorDefinitions="WIN32;_DEBUG;_CONSOLE"
 				MinimalRebuild="true"
 				BasicRuntimeChecks="3"
@@ -123,7 +123,7 @@
 			<Tool
 				Name="VCCLCompilerTool"
 				Optimization="0"
-				AdditionalIncludeDirectories="../src;../src/phreeqcpp;../src/phreeqcpp/PhreeqcKeywords"
+				AdditionalIncludeDirectories="../src;../src/phreeqcpp;../src/phreeqcpp/common;../src/phreeqcpp/PhreeqcKeywords"
 				PreprocessorDefinitions="WIN32;_DEBUG;_CONSOLE"
 				MinimalRebuild="true"
 				BasicRuntimeChecks="3"
@@ -202,7 +202,7 @@
 			/>
 			<Tool
 				Name="VCCLCompilerTool"
-				AdditionalIncludeDirectories="../src;../src/phreeqcpp;../src/phreeqcpp/PhreeqcKeywords"
+				AdditionalIncludeDirectories="../src;../src/phreeqcpp;../src/phreeqcpp/common;../src/phreeqcpp/PhreeqcKeywords"
 				PreprocessorDefinitions="WIN32;NDEBUG;_CONSOLE"
 				RuntimeLibrary="0"
 				UsePrecompiledHeader="0"
@@ -282,7 +282,7 @@
 			/>
 			<Tool
 				Name="VCCLCompilerTool"
-				AdditionalIncludeDirectories="../src;../src/phreeqcpp;../src/phreeqcpp/PhreeqcKeywords"
+				AdditionalIncludeDirectories="../src;../src/phreeqcpp;../src/phreeqcpp/common;../src/phreeqcpp/PhreeqcKeywords"
 				PreprocessorDefinitions="WIN32;NDEBUG;_CONSOLE"
 				RuntimeLibrary="0"
 				UsePrecompiledHeader="0"
@@ -361,7 +361,7 @@
 			<Tool
 				Name="VCCLCompilerTool"
 				Optimization="0"
-				AdditionalIncludeDirectories="../src;../src/phreeqcpp;../src/phreeqcpp/PhreeqcKeywords"
+				AdditionalIncludeDirectories="../src;../src/phreeqcpp;../src/phreeqcpp/common;../src/phreeqcpp/PhreeqcKeywords"
 				PreprocessorDefinitions="WIN32;_DEBUG;_CONSOLE"
 				MinimalRebuild="true"
 				BasicRuntimeChecks="3"
@@ -441,7 +441,7 @@
 			<Tool
 				Name="VCCLCompilerTool"
 				Optimization="0"
-				AdditionalIncludeDirectories="../src;../src/phreeqcpp;../src/phreeqcpp/PhreeqcKeywords"
+				AdditionalIncludeDirectories="../src;../src/phreeqcpp;../src/phreeqcpp/common;../src/phreeqcpp/PhreeqcKeywords"
 				PreprocessorDefinitions="WIN32;_DEBUG;_CONSOLE"
 				MinimalRebuild="true"
 				BasicRuntimeChecks="3"
@@ -520,7 +520,7 @@
 			/>
 			<Tool
 				Name="VCCLCompilerTool"
-				AdditionalIncludeDirectories="../src;../src/phreeqcpp;../src/phreeqcpp/PhreeqcKeywords"
+				AdditionalIncludeDirectories="../src;../src/phreeqcpp;../src/phreeqcpp/common;../src/phreeqcpp/PhreeqcKeywords"
 				PreprocessorDefinitions="WIN32;NDEBUG;_CONSOLE"
 				RuntimeLibrary="0"
 				UsePrecompiledHeader="0"
@@ -600,7 +600,7 @@
 			/>
 			<Tool
 				Name="VCCLCompilerTool"
-				AdditionalIncludeDirectories="../src;../src/phreeqcpp;../src/phreeqcpp/PhreeqcKeywords"
+				AdditionalIncludeDirectories="../src;../src/phreeqcpp;../src/phreeqcpp/common;../src/phreeqcpp/PhreeqcKeywords"
 				PreprocessorDefinitions="WIN32;NDEBUG;_CONSOLE"
 				RuntimeLibrary="0"
 				UsePrecompiledHeader="0"
@@ -679,7 +679,7 @@
 			/>
 			<Tool
 				Name="VCCLCompilerTool"
-				AdditionalIncludeDirectories="../src;../src/phreeqcpp;../src/phreeqcpp/PhreeqcKeywords"
+				AdditionalIncludeDirectories="../src;../src/phreeqcpp;../src/phreeqcpp/common;../src/phreeqcpp/PhreeqcKeywords"
 				PreprocessorDefinitions="WIN32;NDEBUG;_CONSOLE"
 				RuntimeLibrary="0"
 				UsePrecompiledHeader="0"
@@ -760,7 +760,7 @@
 			/>
 			<Tool
 				Name="VCCLCompilerTool"
-				AdditionalIncludeDirectories="../src;../src/phreeqcpp;../src/phreeqcpp/PhreeqcKeywords"
+				AdditionalIncludeDirectories="../src;../src/phreeqcpp;../src/phreeqcpp/common;../src/phreeqcpp/PhreeqcKeywords"
 				PreprocessorDefinitions="WIN32;NDEBUG;_CONSOLE"
 				RuntimeLibrary="2"
 				UsePrecompiledHeader="0"
@@ -839,7 +839,7 @@
 			<Tool
 				Name="VCCLCompilerTool"
 				Optimization="0"
-				AdditionalIncludeDirectories="../src;../src/phreeqcpp;../src/phreeqcpp/PhreeqcKeywords"
+				AdditionalIncludeDirectories="../src;../src/phreeqcpp;../src/phreeqcpp/common;../src/phreeqcpp/PhreeqcKeywords"
 				PreprocessorDefinitions="WIN32;_DEBUG;_CONSOLE"
 				MinimalRebuild="true"
 				BasicRuntimeChecks="3"
@@ -920,7 +920,7 @@
 			<Tool
 				Name="VCCLCompilerTool"
 				Optimization="0"
-				AdditionalIncludeDirectories="../src;../src/phreeqcpp;../src/phreeqcpp/PhreeqcKeywords"
+				AdditionalIncludeDirectories="../src;../src/phreeqcpp;../src/phreeqcpp/common;../src/phreeqcpp/PhreeqcKeywords"
 				PreprocessorDefinitions="WIN32;_DEBUG;_CONSOLE"
 				MinimalRebuild="false"
 				BasicRuntimeChecks="0"
diff --git a/tests/test_f90.vfproj b/tests/test_f90.vfproj
index 54e3f73c..50106af2 100644
--- a/tests/test_f90.vfproj
+++ b/tests/test_f90.vfproj
@@ -5,7 +5,7 @@
 		<Platform Name="x64"/></Platforms>
 	<Configurations>
 		<Configuration Name="Debug|Win32" OutputDirectory="$(SolutionDir)$(ConfigurationName)">
-				<Tool Name="VFFortranCompilerTool" SuppressStartupBanner="true" DebugInformationFormat="debugEnabled" Optimization="optimizeDisabled" AdditionalIncludeDirectories="../src" Interfaces="true" WarnInterfaces="true" Traceback="true" BoundsCheck="true" RuntimeLibrary="rtMultiThreadedDebug"/>
+				<Tool Name="VFFortranCompilerTool" SuppressStartupBanner="true" DebugInformationFormat="debugEnabled" Optimization="optimizeDisabled" Preprocess="preprocessYes" AdditionalIncludeDirectories="../src" Interfaces="true" WarnInterfaces="true" Traceback="true" BoundsCheck="true" RuntimeLibrary="rtMultiThreadedDebug"/>
 				<Tool Name="VFLinkerTool" LinkIncremental="linkIncrementalNo" SuppressStartupBanner="true" AdditionalLibraryDirectories="../lib" GenerateDebugInformation="true" SubSystem="subSystemConsole" AdditionalDependencies="IPhreeqcd.lib"/>
 				<Tool Name="VFResourceCompilerTool"/>
 				<Tool Name="VFMidlTool" SuppressStartupBanner="true"/>
@@ -16,7 +16,7 @@
 copy ex2.in ex2"/>
 				<Tool Name="VFManifestTool" SuppressStartupBanner="true"/></Configuration>
 		<Configuration Name="Release|Win32" OutputDirectory="$(SolutionDir)$(ConfigurationName)">
-				<Tool Name="VFFortranCompilerTool" SuppressStartupBanner="true" AdditionalIncludeDirectories="../src"/>
+				<Tool Name="VFFortranCompilerTool" SuppressStartupBanner="true" Preprocess="preprocessYes" AdditionalIncludeDirectories="../src"/>
 				<Tool Name="VFLinkerTool" LinkIncremental="linkIncrementalNo" SuppressStartupBanner="true" AdditionalLibraryDirectories="../lib" SubSystem="subSystemConsole" AdditionalDependencies="IPhreeqc.lib"/>
 				<Tool Name="VFResourceCompilerTool"/>
 				<Tool Name="VFMidlTool" SuppressStartupBanner="true"/>
@@ -27,7 +27,7 @@ copy ex2.in ex2"/>
 copy ex2.in ex2"/>
 				<Tool Name="VFManifestTool" SuppressStartupBanner="true"/></Configuration>
 		<Configuration Name="Debug|x64">
-				<Tool Name="VFFortranCompilerTool" SuppressStartupBanner="true" DebugInformationFormat="debugEnabled" Optimization="optimizeDisabled" AdditionalIncludeDirectories="../src" Interfaces="true" WarnInterfaces="true" Traceback="true" BoundsCheck="true" RuntimeLibrary="rtMultiThreadedDebug"/>
+				<Tool Name="VFFortranCompilerTool" SuppressStartupBanner="true" DebugInformationFormat="debugEnabled" Optimization="optimizeDisabled" Preprocess="preprocessYes" AdditionalIncludeDirectories="../src" Interfaces="true" WarnInterfaces="true" Traceback="true" BoundsCheck="true" RuntimeLibrary="rtMultiThreadedDebug"/>
 				<Tool Name="VFLinkerTool" LinkIncremental="linkIncrementalNo" SuppressStartupBanner="true" AdditionalLibraryDirectories="../libx64" GenerateDebugInformation="true" SubSystem="subSystemConsole" AdditionalDependencies="IPhreeqcd.lib"/>
 				<Tool Name="VFResourceCompilerTool"/>
 				<Tool Name="VFMidlTool" SuppressStartupBanner="true" TargetEnvironment="midlTargetAMD64"/>
@@ -38,7 +38,7 @@ copy ex2.in ex2"/>
 copy ex2.in ex2"/>
 				<Tool Name="VFManifestTool" SuppressStartupBanner="true"/></Configuration>
 		<Configuration Name="Release|x64">
-				<Tool Name="VFFortranCompilerTool" SuppressStartupBanner="true" AdditionalIncludeDirectories="../src"/>
+				<Tool Name="VFFortranCompilerTool" SuppressStartupBanner="true" Preprocess="preprocessYes" AdditionalIncludeDirectories="../src"/>
 				<Tool Name="VFLinkerTool" LinkIncremental="linkIncrementalNo" SuppressStartupBanner="true" AdditionalLibraryDirectories="../libx64" SubSystem="subSystemConsole" AdditionalDependencies="IPhreeqc.lib"/>
 				<Tool Name="VFResourceCompilerTool"/>
 				<Tool Name="VFMidlTool" SuppressStartupBanner="true" TargetEnvironment="midlTargetAMD64"/>
@@ -49,7 +49,7 @@ copy ex2.in ex2"/>
 copy ex2.in ex2"/>
 				<Tool Name="VFManifestTool" SuppressStartupBanner="true"/></Configuration>
 		<Configuration Name="ReleaseDll|Win32" OutputDirectory="$(SolutionDir)$(ConfigurationName)">
-				<Tool Name="VFFortranCompilerTool" SuppressStartupBanner="true" AdditionalIncludeDirectories="../src" RuntimeLibrary="rtMultiThreadedDLL"/>
+				<Tool Name="VFFortranCompilerTool" SuppressStartupBanner="true" Preprocess="preprocessYes" AdditionalIncludeDirectories="../src" RuntimeLibrary="rtMultiThreadedDLL"/>
 				<Tool Name="VFLinkerTool" LinkIncremental="linkIncrementalNo" SuppressStartupBanner="true" AdditionalLibraryDirectories="../dll" SubSystem="subSystemConsole" AdditionalDependencies="IPhreeqc.lib"/>
 				<Tool Name="VFResourceCompilerTool"/>
 				<Tool Name="VFMidlTool" SuppressStartupBanner="true"/>
@@ -60,7 +60,7 @@ copy ex2.in ex2"/>
 copy ex2.in ex2"/>
 				<Tool Name="VFManifestTool" SuppressStartupBanner="true"/></Configuration>
 		<Configuration Name="ReleaseDll|x64">
-				<Tool Name="VFFortranCompilerTool" SuppressStartupBanner="true" AdditionalIncludeDirectories="../src"/>
+				<Tool Name="VFFortranCompilerTool" SuppressStartupBanner="true" Preprocess="preprocessYes" AdditionalIncludeDirectories="../src"/>
 				<Tool Name="VFLinkerTool" LinkIncremental="linkIncrementalNo" SuppressStartupBanner="true" AdditionalLibraryDirectories="../libx64" SubSystem="subSystemConsole" AdditionalDependencies="IPhreeqc.lib"/>
 				<Tool Name="VFResourceCompilerTool"/>
 				<Tool Name="VFMidlTool" SuppressStartupBanner="true" TargetEnvironment="midlTargetAMD64"/>
@@ -71,7 +71,7 @@ copy ex2.in ex2"/>
 copy ex2.in ex2"/>
 				<Tool Name="VFManifestTool" SuppressStartupBanner="true"/></Configuration>
 		<Configuration Name="DebugDll|Win32" OutputDirectory="$(SolutionDir)$(ConfigurationName)">
-				<Tool Name="VFFortranCompilerTool" SuppressStartupBanner="true" DebugInformationFormat="debugEnabled" Optimization="optimizeDisabled" AdditionalIncludeDirectories="../src" Interfaces="true" WarnInterfaces="true" Traceback="true" BoundsCheck="true" RuntimeLibrary="rtMultiThreadedDebugDLL"/>
+				<Tool Name="VFFortranCompilerTool" SuppressStartupBanner="true" DebugInformationFormat="debugEnabled" Optimization="optimizeDisabled" Preprocess="preprocessYes" AdditionalIncludeDirectories="../src" Interfaces="true" WarnInterfaces="true" Traceback="true" BoundsCheck="true" RuntimeLibrary="rtMultiThreadedDebugDLL"/>
 				<Tool Name="VFLinkerTool" LinkIncremental="linkIncrementalNo" SuppressStartupBanner="true" AdditionalLibraryDirectories="../dll" GenerateDebugInformation="true" SubSystem="subSystemConsole" AdditionalDependencies="IPhreeqcd.lib"/>
 				<Tool Name="VFResourceCompilerTool"/>
 				<Tool Name="VFMidlTool" SuppressStartupBanner="true"/>
@@ -82,7 +82,7 @@ copy ex2.in ex2"/>
 copy ex2.in ex2"/>
 				<Tool Name="VFManifestTool" SuppressStartupBanner="true"/></Configuration>
 		<Configuration Name="DebugDll|x64">
-				<Tool Name="VFFortranCompilerTool" SuppressStartupBanner="true" DebugInformationFormat="debugEnabled" Optimization="optimizeDisabled" AdditionalIncludeDirectories="../src" Interfaces="true" WarnInterfaces="true" Traceback="true" BoundsCheck="true" RuntimeLibrary="rtMultiThreadedDebug"/>
+				<Tool Name="VFFortranCompilerTool" SuppressStartupBanner="true" DebugInformationFormat="debugEnabled" Optimization="optimizeDisabled" Preprocess="preprocessYes" AdditionalIncludeDirectories="../src" Interfaces="true" WarnInterfaces="true" Traceback="true" BoundsCheck="true" RuntimeLibrary="rtMultiThreadedDebug"/>
 				<Tool Name="VFLinkerTool" LinkIncremental="linkIncrementalNo" SuppressStartupBanner="true" AdditionalLibraryDirectories="../libx64" GenerateDebugInformation="true" SubSystem="subSystemConsole" AdditionalDependencies="IPhreeqcd.lib"/>
 				<Tool Name="VFResourceCompilerTool"/>
 				<Tool Name="VFMidlTool" SuppressStartupBanner="true" TargetEnvironment="midlTargetAMD64"/>
@@ -93,7 +93,7 @@ copy ex2.in ex2"/>
 copy ex2.in ex2"/>
 				<Tool Name="VFManifestTool" SuppressStartupBanner="true"/></Configuration>
 		<Configuration Name="ReleaseCLR|Win32" OutputDirectory="$(SolutionDir)$(ConfigurationName)">
-				<Tool Name="VFFortranCompilerTool" SuppressStartupBanner="true" AdditionalIncludeDirectories="../src" RuntimeLibrary="rtMultiThreadedDLL"/>
+				<Tool Name="VFFortranCompilerTool" SuppressStartupBanner="true" Preprocess="preprocessYes" AdditionalIncludeDirectories="../src" RuntimeLibrary="rtMultiThreadedDLL"/>
 				<Tool Name="VFLinkerTool" LinkIncremental="linkIncrementalNo" SuppressStartupBanner="true" AdditionalLibraryDirectories="../clr" SubSystem="subSystemConsole" AdditionalDependencies="IPhreeqc.lib"/>
 				<Tool Name="VFResourceCompilerTool"/>
 				<Tool Name="VFMidlTool" SuppressStartupBanner="true"/>
@@ -104,7 +104,7 @@ copy ex2.in ex2"/>
 copy ex2.in ex2"/>
 				<Tool Name="VFManifestTool" SuppressStartupBanner="true"/></Configuration>
 		<Configuration Name="ReleaseCLR|x64">
-				<Tool Name="VFFortranCompilerTool" SuppressStartupBanner="true" AdditionalIncludeDirectories="../src"/>
+				<Tool Name="VFFortranCompilerTool" SuppressStartupBanner="true" Preprocess="preprocessYes" AdditionalIncludeDirectories="../src"/>
 				<Tool Name="VFLinkerTool" LinkIncremental="linkIncrementalNo" SuppressStartupBanner="true" AdditionalLibraryDirectories="../clrx64" SubSystem="subSystemConsole" AdditionalDependencies="IPhreeqc.lib"/>
 				<Tool Name="VFResourceCompilerTool"/>
 				<Tool Name="VFMidlTool" SuppressStartupBanner="true" TargetEnvironment="midlTargetAMD64"/>
@@ -115,7 +115,7 @@ copy ex2.in ex2"/>
 copy ex2.in ex2"/>
 				<Tool Name="VFManifestTool" SuppressStartupBanner="true"/></Configuration>
 		<Configuration Name="DebugCLR|Win32" OutputDirectory="$(SolutionDir)$(ConfigurationName)">
-				<Tool Name="VFFortranCompilerTool" SuppressStartupBanner="true" DebugInformationFormat="debugEnabled" Optimization="optimizeDisabled" AdditionalIncludeDirectories="../src" Interfaces="true" WarnInterfaces="true" Traceback="true" BoundsCheck="true" RuntimeLibrary="rtMultiThreadedDebugDLL"/>
+				<Tool Name="VFFortranCompilerTool" SuppressStartupBanner="true" DebugInformationFormat="debugEnabled" Optimization="optimizeDisabled" Preprocess="preprocessYes" AdditionalIncludeDirectories="../src" Interfaces="true" WarnInterfaces="true" Traceback="true" BoundsCheck="true" RuntimeLibrary="rtMultiThreadedDebugDLL"/>
 				<Tool Name="VFLinkerTool" LinkIncremental="linkIncrementalNo" SuppressStartupBanner="true" AdditionalLibraryDirectories="../clr" GenerateDebugInformation="true" SubSystem="subSystemConsole" AdditionalDependencies="IPhreeqcd.lib"/>
 				<Tool Name="VFResourceCompilerTool"/>
 				<Tool Name="VFMidlTool" SuppressStartupBanner="true"/>
@@ -126,7 +126,7 @@ copy ex2.in ex2"/>
 copy ex2.in ex2"/>
 				<Tool Name="VFManifestTool" SuppressStartupBanner="true"/></Configuration>
 		<Configuration Name="DebugCLR|x64">
-				<Tool Name="VFFortranCompilerTool" SuppressStartupBanner="true" DebugInformationFormat="debugEnabled" Optimization="optimizeDisabled" AdditionalIncludeDirectories="../src" Interfaces="true" WarnInterfaces="true" Traceback="true" BoundsCheck="true" RuntimeLibrary="rtMultiThreadedDebug"/>
+				<Tool Name="VFFortranCompilerTool" SuppressStartupBanner="true" DebugInformationFormat="debugEnabled" Optimization="optimizeDisabled" Preprocess="preprocessYes" AdditionalIncludeDirectories="../src" Interfaces="true" WarnInterfaces="true" Traceback="true" BoundsCheck="true" RuntimeLibrary="rtMultiThreadedDebug"/>
 				<Tool Name="VFLinkerTool" LinkIncremental="linkIncrementalNo" SuppressStartupBanner="true" AdditionalLibraryDirectories="../clrx64" GenerateDebugInformation="true" SubSystem="subSystemConsole" AdditionalDependencies="IPhreeqcd.lib"/>
 				<Tool Name="VFResourceCompilerTool"/>
 				<Tool Name="VFMidlTool" SuppressStartupBanner="true" TargetEnvironment="midlTargetAMD64"/>
@@ -140,6 +140,7 @@ copy ex2.in ex2"/>
 		<Filter Name="Header Files" Filter="fi;fd"/>
 		<Filter Name="Resource Files" Filter="rc;ico;cur;bmp;dlg;rc2;rct;bin;rgs;gif;jpg;jpeg;jpe"/>
 		<Filter Name="Source Files" Filter="f90;for;f;fpp;ftn;def;odl;idl">
+		<File RelativePath="..\src\IPhreeqc_interface.F90"/>
 		<File RelativePath=".\main.f90"/>
 		<File RelativePath=".\test_f90.f90"/></Filter>
 		<File RelativePath=".\ReadMe.txt"/></Files>
diff --git a/unit/unit.vcproj b/unit/unit.vcproj
index 1187898c..d1adf3a7 100644
--- a/unit/unit.vcproj
+++ b/unit/unit.vcproj
@@ -48,7 +48,7 @@
 				Name="VCCLCompilerTool"
 				AdditionalOptions="/MP"
 				Optimization="0"
-				AdditionalIncludeDirectories="&quot;$(DEV_CPPUNIT_1_10)/include&quot;;../src;../src/phreeqcpp;../src/phreeqcpp/PhreeqcKeywords"
+				AdditionalIncludeDirectories="&quot;$(DEV_CPPUNIT_1_10)/include&quot;;../src;../src/phreeqcpp;../src/phreeqcpp/common;../src/phreeqcpp/PhreeqcKeywords"
 				PreprocessorDefinitions="CPPUNIT;WIN32;_DEBUG;_CONSOLE"
 				MinimalRebuild="true"
 				BasicRuntimeChecks="3"
@@ -133,7 +133,7 @@
 				Name="VCCLCompilerTool"
 				AdditionalOptions="/MP"
 				Optimization="0"
-				AdditionalIncludeDirectories="&quot;$(DEV_CPPUNIT_1_10)/include&quot;;../src;../src/phreeqcpp;../src/phreeqcpp/PhreeqcKeywords"
+				AdditionalIncludeDirectories="&quot;$(DEV_CPPUNIT_1_10)/include&quot;;../src;../src/phreeqcpp;../src/phreeqcpp/common;../src/phreeqcpp/PhreeqcKeywords"
 				PreprocessorDefinitions="CPPUNIT;WIN32;_DEBUG;_CONSOLE"
 				BasicRuntimeChecks="3"
 				RuntimeLibrary="3"
@@ -212,7 +212,7 @@
 				AdditionalOptions="/MP"
 				Optimization="2"
 				InlineFunctionExpansion="1"
-				AdditionalIncludeDirectories="&quot;$(DEV_CPPUNIT_1_10)/include&quot;;../src;../src/phreeqcpp;../src/phreeqcpp/PhreeqcKeywords"
+				AdditionalIncludeDirectories="&quot;$(DEV_CPPUNIT_1_10)/include&quot;;../src;../src/phreeqcpp;../src/phreeqcpp/common;../src/phreeqcpp/PhreeqcKeywords"
 				PreprocessorDefinitions="CPPUNIT;WIN32;NDEBUG;_CONSOLE"
 				StringPooling="true"
 				RuntimeLibrary="2"
@@ -293,7 +293,7 @@
 			<Tool
 				Name="VCCLCompilerTool"
 				AdditionalOptions="/MP"
-				AdditionalIncludeDirectories="&quot;$(DEV_CPPUNIT_1_10)/include&quot;;../src;../src/phreeqcpp;../src/phreeqcpp/PhreeqcKeywords"
+				AdditionalIncludeDirectories="&quot;$(DEV_CPPUNIT_1_10)/include&quot;;../src;../src/phreeqcpp;../src/phreeqcpp/common;../src/phreeqcpp/PhreeqcKeywords"
 				PreprocessorDefinitions="CPPUNIT;WIN32;NDEBUG;_CONSOLE"
 				RuntimeLibrary="2"
 			/>
@@ -695,8 +695,44 @@
 						>
 					</File>
 					<File
-						RelativePath="..\src\phreeqcpp\Parser.cxx"
+						RelativePath="..\src\phreeqcpp\common\Parser.cxx"
 						>
+						<FileConfiguration
+							Name="Debug|Win32"
+							>
+							<Tool
+								Name="VCCLCompilerTool"
+								ObjectFile="$(IntDir)\$(InputName)1.obj"
+								XMLDocumentationFileName="$(IntDir)\$(InputName)1.xdc"
+							/>
+						</FileConfiguration>
+						<FileConfiguration
+							Name="Debug|x64"
+							>
+							<Tool
+								Name="VCCLCompilerTool"
+								ObjectFile="$(IntDir)\$(InputName)1.obj"
+								XMLDocumentationFileName="$(IntDir)\$(InputName)1.xdc"
+							/>
+						</FileConfiguration>
+						<FileConfiguration
+							Name="Release|Win32"
+							>
+							<Tool
+								Name="VCCLCompilerTool"
+								ObjectFile="$(IntDir)\$(InputName)1.obj"
+								XMLDocumentationFileName="$(IntDir)\$(InputName)1.xdc"
+							/>
+						</FileConfiguration>
+						<FileConfiguration
+							Name="Release|x64"
+							>
+							<Tool
+								Name="VCCLCompilerTool"
+								ObjectFile="$(IntDir)\$(InputName)1.obj"
+								XMLDocumentationFileName="$(IntDir)\$(InputName)1.xdc"
+							/>
+						</FileConfiguration>
 					</File>
 					<File
 						RelativePath="..\src\phreeqcpp\PBasic.cpp"
@@ -711,12 +747,84 @@
 						>
 					</File>
 					<File
-						RelativePath="..\src\phreeqcpp\PHRQ_base.cxx"
+						RelativePath="..\src\phreeqcpp\common\PHRQ_base.cxx"
 						>
+						<FileConfiguration
+							Name="Debug|Win32"
+							>
+							<Tool
+								Name="VCCLCompilerTool"
+								ObjectFile="$(IntDir)\$(InputName)1.obj"
+								XMLDocumentationFileName="$(IntDir)\$(InputName)1.xdc"
+							/>
+						</FileConfiguration>
+						<FileConfiguration
+							Name="Debug|x64"
+							>
+							<Tool
+								Name="VCCLCompilerTool"
+								ObjectFile="$(IntDir)\$(InputName)1.obj"
+								XMLDocumentationFileName="$(IntDir)\$(InputName)1.xdc"
+							/>
+						</FileConfiguration>
+						<FileConfiguration
+							Name="Release|Win32"
+							>
+							<Tool
+								Name="VCCLCompilerTool"
+								ObjectFile="$(IntDir)\$(InputName)1.obj"
+								XMLDocumentationFileName="$(IntDir)\$(InputName)1.xdc"
+							/>
+						</FileConfiguration>
+						<FileConfiguration
+							Name="Release|x64"
+							>
+							<Tool
+								Name="VCCLCompilerTool"
+								ObjectFile="$(IntDir)\$(InputName)1.obj"
+								XMLDocumentationFileName="$(IntDir)\$(InputName)1.xdc"
+							/>
+						</FileConfiguration>
 					</File>
 					<File
-						RelativePath="..\src\phreeqcpp\PHRQ_io.cpp"
+						RelativePath="..\src\phreeqcpp\common\PHRQ_io.cpp"
 						>
+						<FileConfiguration
+							Name="Debug|Win32"
+							>
+							<Tool
+								Name="VCCLCompilerTool"
+								ObjectFile="$(IntDir)\$(InputName)1.obj"
+								XMLDocumentationFileName="$(IntDir)\$(InputName)1.xdc"
+							/>
+						</FileConfiguration>
+						<FileConfiguration
+							Name="Debug|x64"
+							>
+							<Tool
+								Name="VCCLCompilerTool"
+								ObjectFile="$(IntDir)\$(InputName)1.obj"
+								XMLDocumentationFileName="$(IntDir)\$(InputName)1.xdc"
+							/>
+						</FileConfiguration>
+						<FileConfiguration
+							Name="Release|Win32"
+							>
+							<Tool
+								Name="VCCLCompilerTool"
+								ObjectFile="$(IntDir)\$(InputName)1.obj"
+								XMLDocumentationFileName="$(IntDir)\$(InputName)1.xdc"
+							/>
+						</FileConfiguration>
+						<FileConfiguration
+							Name="Release|x64"
+							>
+							<Tool
+								Name="VCCLCompilerTool"
+								ObjectFile="$(IntDir)\$(InputName)1.obj"
+								XMLDocumentationFileName="$(IntDir)\$(InputName)1.xdc"
+							/>
+						</FileConfiguration>
 					</File>
 					<File
 						RelativePath="..\src\phreeqcpp\PHRQ_io_output.cpp"
@@ -871,8 +979,44 @@
 						>
 					</File>
 					<File
-						RelativePath="..\src\phreeqcpp\Utils.cxx"
+						RelativePath="..\src\phreeqcpp\common\Utils.cxx"
 						>
+						<FileConfiguration
+							Name="Debug|Win32"
+							>
+							<Tool
+								Name="VCCLCompilerTool"
+								ObjectFile="$(IntDir)\$(InputName)1.obj"
+								XMLDocumentationFileName="$(IntDir)\$(InputName)1.xdc"
+							/>
+						</FileConfiguration>
+						<FileConfiguration
+							Name="Debug|x64"
+							>
+							<Tool
+								Name="VCCLCompilerTool"
+								ObjectFile="$(IntDir)\$(InputName)1.obj"
+								XMLDocumentationFileName="$(IntDir)\$(InputName)1.xdc"
+							/>
+						</FileConfiguration>
+						<FileConfiguration
+							Name="Release|Win32"
+							>
+							<Tool
+								Name="VCCLCompilerTool"
+								ObjectFile="$(IntDir)\$(InputName)1.obj"
+								XMLDocumentationFileName="$(IntDir)\$(InputName)1.xdc"
+							/>
+						</FileConfiguration>
+						<FileConfiguration
+							Name="Release|x64"
+							>
+							<Tool
+								Name="VCCLCompilerTool"
+								ObjectFile="$(IntDir)\$(InputName)1.obj"
+								XMLDocumentationFileName="$(IntDir)\$(InputName)1.xdc"
+							/>
+						</FileConfiguration>
 					</File>
 				</Filter>
 			</Filter>
@@ -1048,7 +1192,7 @@
 						>
 					</File>
 					<File
-						RelativePath="..\src\phreeqcpp\Parser.h"
+						RelativePath="..\src\phreeqcpp\common\Parser.h"
 						>
 					</File>
 					<File
@@ -1064,15 +1208,15 @@
 						>
 					</File>
 					<File
-						RelativePath="..\src\phreeqcpp\PHRQ_base.h"
+						RelativePath="..\src\phreeqcpp\common\PHRQ_base.h"
 						>
 					</File>
 					<File
-						RelativePath="..\src\phreeqcpp\PHRQ_io.h"
+						RelativePath="..\src\phreeqcpp\common\PHRQ_io.h"
 						>
 					</File>
 					<File
-						RelativePath="..\src\phreeqcpp\phrqtype.h"
+						RelativePath="..\src\phreeqcpp\common\phrqtype.h"
 						>
 					</File>
 					<File
@@ -1168,7 +1312,7 @@
 						>
 					</File>
 					<File
-						RelativePath="..\src\phreeqcpp\Utils.h"
+						RelativePath="..\src\phreeqcpp\common\Utils.h"
 						>
 					</File>
 				</Filter>