diff --git a/samples/SampleWebApp/Web.config b/samples/SampleWebApp/Web.config
index 9ee9f48..d58e445 100644
--- a/samples/SampleWebApp/Web.config
+++ b/samples/SampleWebApp/Web.config
@@ -14,7 +14,7 @@
       <!-- <add name="Environment" mode="Expand" type="Microsoft.Configuration.ConfigurationBuilders.EnvironmentConfigBuilder, Microsoft.Configuration.ConfigurationBuilders.Environment, Version=1.0.0.0, Culture=neutral"/> -->
       <add name="Secrets" userSecretsFile="~/App_Data/secrets.xml" mode="Greedy" type="Microsoft.Configuration.ConfigurationBuilders.UserSecretsConfigBuilder, Microsoft.Configuration.ConfigurationBuilders.UserSecrets, Version=1.0.0.0, Culture=neutral" />
       <add name="SimpleJson" jsonFile="~/App_Data/settings.json" ignoreMissingFile="true" type="Microsoft.Configuration.ConfigurationBuilders.SimpleJsonConfigBuilder, Microsoft.Configuration.ConfigurationBuilders.Json, Version=1.0.0.0, Culture=neutral" />
-      <add name="KeyPerFile" directoryPath="~/../KeyPerFileSampleRoot" mode="Greedy" keyDelimiter="--" type="Microsoft.Configuration.ConfigurationBuilders.KeyPerFileConfigBuilder, Microsoft.Configuration.ConfigurationBuilders.KeyPerFile, Version=1.0.0.0, Culture=neutral" />
+      <add name="KeyPerFile" directoryPath="~/../KeyPerFileSampleRoot" mode="Strict" keyDelimiter="--" type="Microsoft.Configuration.ConfigurationBuilders.KeyPerFileConfigBuilder, Microsoft.Configuration.ConfigurationBuilders.KeyPerFile, Version=1.0.0.0, Culture=neutral" />
     </builders>
   </configBuilders>
 
@@ -32,6 +32,10 @@
     <add key="jsonConnectionString1" value="WILL be replaced by 'SimpleJson' in 'Flat' jsonMode." />
     <add key="jsonConnectionString2" value="WILL NOT be replaced by 'SimpleJson' in 'Sectional' jsonMode." />
     <add key="jsonCustomSetting1" value="Will be replaced by 'SimpleJson' with prefix='customSettings:' and stripPrefix='true'." />
+    <add key="SecretFromFile1" value="This will be replaced by KeyPerFile." />
+    <add key="SECRETFROMFILE2" value="As will this one." />
+    <add key="SubFeature--FeatureSecretA" value="This will be replaced by KeyPerFile if keyDelimiter is set to '--'." />
+    <add key="ignore.secretfromfile3" value="This value should be left alone." />
   </appSettings>
 
   <connectionStrings configBuilders="SimpleJson">
diff --git a/src/KeyPerFile/KeyPerFileConfigBuilder.cs b/src/KeyPerFile/KeyPerFileConfigBuilder.cs
index 68a75b1..ac3d77d 100644
--- a/src/KeyPerFile/KeyPerFileConfigBuilder.cs
+++ b/src/KeyPerFile/KeyPerFileConfigBuilder.cs
@@ -88,10 +88,19 @@ public override ICollection<KeyValuePair<string, string>> GetAllValues(string pr
         /// <returns>The value corresponding to the given 'key' or null if no value is found.</returns>
         public override string GetValue(string key)
         {
-            if (_allValues != null && _allValues.TryGetValue(key, out string val))
-                return val;
+            string filename = key;
+            if (!String.IsNullOrEmpty(KeyDelimiter))
+                filename = filename.Replace(KeyDelimiter, Path.DirectorySeparatorChar.ToString());
 
-            return null;
+            if (!String.IsNullOrWhiteSpace(IgnorePrefix))
+            {
+                foreach (var pathPart in filename.Split(new char[] { Path.DirectorySeparatorChar })) {
+                    if (pathPart.StartsWith(IgnorePrefix, StringComparison.OrdinalIgnoreCase))
+                        return null;
+                }
+            }
+
+            return ReadValueFromFile(Path.Combine(DirectoryPath, filename));
         }
 
         private IDictionary<string, string> ReadAllValues(string root, string prefix, IDictionary<string, string> values)
@@ -107,7 +116,7 @@ private IDictionary<string, string> ReadAllValues(string root, string prefix, ID
             {
                 foreach (var sub in di.EnumerateDirectories())
                 {
-                    if (!String.IsNullOrWhiteSpace(IgnorePrefix) && sub.Name.StartsWith(IgnorePrefix))
+                    if (!String.IsNullOrWhiteSpace(IgnorePrefix) && sub.Name.StartsWith(IgnorePrefix, StringComparison.OrdinalIgnoreCase))
                         continue;
 
                     ReadAllValues(sub.FullName, sub.Name + KeyDelimiter, values);
@@ -116,7 +125,7 @@ private IDictionary<string, string> ReadAllValues(string root, string prefix, ID
 
             foreach (var file in di.EnumerateFiles())
             {
-                if (!String.IsNullOrWhiteSpace(IgnorePrefix) && file.Name.StartsWith(IgnorePrefix))
+                if (!String.IsNullOrWhiteSpace(IgnorePrefix) && file.Name.StartsWith(IgnorePrefix, StringComparison.OrdinalIgnoreCase))
                     continue;
 
                 string key = prefix + file.Name;
diff --git a/src/packages/ConfigurationBuilders.Azure.nupkg/Microsoft.Configuration.ConfigurationBuilders.Azure.nuproj b/src/packages/ConfigurationBuilders.Azure.nupkg/Microsoft.Configuration.ConfigurationBuilders.Azure.nuproj
index c270c05..a47d673 100644
--- a/src/packages/ConfigurationBuilders.Azure.nupkg/Microsoft.Configuration.ConfigurationBuilders.Azure.nuproj
+++ b/src/packages/ConfigurationBuilders.Azure.nupkg/Microsoft.Configuration.ConfigurationBuilders.Azure.nuproj
@@ -40,6 +40,9 @@
         <NuGetContent Include="..\ConfigurationBuilders.Base.nupkg\shared\tools\Net471\pp\*.ps1">
           <Destination>tools\Net471\</Destination>
         </NuGetContent>
+        <NuGetContent Include="README.txt">
+          <Destination>README.txt</Destination>
+        </NuGetContent>
     </ItemGroup>
     <Import Project="$(RepositoryRoot)Tools\NuGetProj.targets"/>
 </Project>
\ No newline at end of file
diff --git a/src/packages/ConfigurationBuilders.Azure.nupkg/README.txt b/src/packages/ConfigurationBuilders.Azure.nupkg/README.txt
new file mode 100644
index 0000000..ee71d33
--- /dev/null
+++ b/src/packages/ConfigurationBuilders.Azure.nupkg/README.txt
@@ -0,0 +1,24 @@
+########################################################################################################################
+##                                                                                                                    ##
+##                                Microsoft.Configuration.ConfigurationBuilders.Azure                                 ##
+##                                                                                                                    ##
+########################################################################################################################
+
+WARNING: Double check config builder attributes in your configuraiton files. Some attributes may have been changed
+         when upgrading this package.
+
+If this is the first time you are installing this configuration builder into your
+project, feel free to click the 'X' on this tab to close and continue on.
+
+However, if you are updating this package from a version earlier than 1.0.2... you may want to double check the
+declarations for your config builders, because we might have lost changes you made to the default declarations
+that were created during the original install.
+
+The upgrade mechanism for nuget is actually just Uninstall/Install, and prior to 1.0.2, this package would delete
+the config builder declaration that it created upon install. Makes sense. But if you made any changes to that
+declaration without changing the name of it, we didn't bother to make note of that. So the 'install' phase of
+updating will declare the default config builder with the default parameters again. (If you did change the name
+to something other than the default - AzureKeyVault - then we did not delete your declaration when uninstalling.)
+
+Starting in version 1.0.2, we have a way to stash old declarations aside and restore them upon install. Sorry for the
+inconvenience. There should be no such troubles with future upgrades.
diff --git a/src/packages/ConfigurationBuilders.Environment.nupkg/Microsoft.Configuration.ConfigurationBuilders.Environment.nuproj b/src/packages/ConfigurationBuilders.Environment.nupkg/Microsoft.Configuration.ConfigurationBuilders.Environment.nuproj
index b7449bc..2f63d4a 100644
--- a/src/packages/ConfigurationBuilders.Environment.nupkg/Microsoft.Configuration.ConfigurationBuilders.Environment.nuproj
+++ b/src/packages/ConfigurationBuilders.Environment.nupkg/Microsoft.Configuration.ConfigurationBuilders.Environment.nuproj
@@ -40,6 +40,9 @@
         <NuGetContent Include="..\ConfigurationBuilders.Base.nupkg\shared\tools\Net471\pp\*.ps1">
           <Destination>tools\Net471\</Destination>
         </NuGetContent>
+        <NuGetContent Include="README.txt">
+          <Destination>README.txt</Destination>
+        </NuGetContent>
     </ItemGroup>
     <Import Project="$(RepositoryRoot)Tools\NuGetProj.targets"/>
 </Project>
\ No newline at end of file
diff --git a/src/packages/ConfigurationBuilders.Environment.nupkg/README.txt b/src/packages/ConfigurationBuilders.Environment.nupkg/README.txt
new file mode 100644
index 0000000..a569858
--- /dev/null
+++ b/src/packages/ConfigurationBuilders.Environment.nupkg/README.txt
@@ -0,0 +1,24 @@
+########################################################################################################################
+##                                                                                                                    ##
+##                             Microsoft.Configuration.ConfigurationBuilders.Environment                              ##
+##                                                                                                                    ##
+########################################################################################################################
+
+WARNING: Double check config builder attributes in your configuraiton files. Some attributes may have been changed
+         when upgrading this package.
+
+If this is the first time you are installing this configuration builder into your
+project, feel free to click the 'X' on this tab to close and continue on.
+
+However, if you are updating this package from a version earlier than 1.0.2... you may want to double check the
+declarations for your config builders, because we might have lost changes you made to the default declarations
+that were created during the original install.
+
+The upgrade mechanism for nuget is actually just Uninstall/Install, and prior to 1.0.2, this package would delete
+the config builder declaration that it created upon install. Makes sense. But if you made any changes to that
+declaration without changing the name of it, we didn't bother to make note of that. So the 'install' phase of
+updating will declare the default config builder with the default parameters again. (If you did change the name
+to something other than the default - Environment - then we did not delete your declaration when uninstalling.)
+
+Starting in version 1.0.2, we have a way to stash old declarations aside and restore them upon install. Sorry for the
+inconvenience. There should be no such troubles with future upgrades.
diff --git a/src/packages/ConfigurationBuilders.Json.nupkg/Microsoft.Configuration.ConfigurationBuilders.Json.nuproj b/src/packages/ConfigurationBuilders.Json.nupkg/Microsoft.Configuration.ConfigurationBuilders.Json.nuproj
index 80a0ec0..00be497 100644
--- a/src/packages/ConfigurationBuilders.Json.nupkg/Microsoft.Configuration.ConfigurationBuilders.Json.nuproj
+++ b/src/packages/ConfigurationBuilders.Json.nupkg/Microsoft.Configuration.ConfigurationBuilders.Json.nuproj
@@ -40,6 +40,9 @@
         <NuGetContent Include="..\ConfigurationBuilders.Base.nupkg\shared\tools\Net471\pp\*.ps1">
           <Destination>tools\Net471\</Destination>
         </NuGetContent>
+        <NuGetContent Include="README.txt">
+          <Destination>README.txt</Destination>
+        </NuGetContent>
     </ItemGroup>
     <Import Project="$(RepositoryRoot)Tools\NuGetProj.targets"/>
 </Project>
\ No newline at end of file
diff --git a/src/packages/ConfigurationBuilders.Json.nupkg/README.txt b/src/packages/ConfigurationBuilders.Json.nupkg/README.txt
new file mode 100644
index 0000000..5e064bc
--- /dev/null
+++ b/src/packages/ConfigurationBuilders.Json.nupkg/README.txt
@@ -0,0 +1,24 @@
+########################################################################################################################
+##                                                                                                                    ##
+##                                Microsoft.Configuration.ConfigurationBuilders.Json                                  ##
+##                                                                                                                    ##
+########################################################################################################################
+
+WARNING: Double check config builder attributes in your configuraiton files. Some attributes may have been changed
+         when upgrading this package.
+
+If this is the first time you are installing this configuration builder into your
+project, feel free to click the 'X' on this tab to close and continue on.
+
+However, if you are updating this package from a version earlier than 1.0.2... you may want to double check the
+declarations for your config builders, because we might have lost changes you made to the default declarations
+that were created during the original install.
+
+The upgrade mechanism for nuget is actually just Uninstall/Install, and prior to 1.0.2, this package would delete
+the config builder declaration that it created upon install. Makes sense. But if you made any changes to that
+declaration without changing the name of it, we didn't bother to make note of that. So the 'install' phase of
+updating will declare the default config builder with the default parameters again. (If you did change the name
+to something other than the default - SimpleJson - then we did not delete your declaration when uninstalling.)
+
+Starting in version 1.0.2, we have a way to stash old declarations aside and restore them upon install. Sorry for the
+inconvenience. There should be no such troubles with future upgrades.
diff --git a/src/packages/ConfigurationBuilders.UserSecrets.nupkg/Microsoft.Configuration.ConfigurationBuilders.UserSecrets.nuproj b/src/packages/ConfigurationBuilders.UserSecrets.nupkg/Microsoft.Configuration.ConfigurationBuilders.UserSecrets.nuproj
index 9442d48..61bde06 100644
--- a/src/packages/ConfigurationBuilders.UserSecrets.nupkg/Microsoft.Configuration.ConfigurationBuilders.UserSecrets.nuproj
+++ b/src/packages/ConfigurationBuilders.UserSecrets.nupkg/Microsoft.Configuration.ConfigurationBuilders.UserSecrets.nuproj
@@ -40,6 +40,9 @@
         <NuGetContent Include="..\ConfigurationBuilders.Base.nupkg\shared\tools\Net471\pp\*.ps1">
           <Destination>tools\Net471\</Destination>
         </NuGetContent>
+        <NuGetContent Include="README.txt">
+          <Destination>README.txt</Destination>
+        </NuGetContent>
     </ItemGroup>
     <Import Project="$(RepositoryRoot)Tools\NuGetProj.targets"/>
 </Project>
\ No newline at end of file
diff --git a/src/packages/ConfigurationBuilders.UserSecrets.nupkg/README.txt b/src/packages/ConfigurationBuilders.UserSecrets.nupkg/README.txt
new file mode 100644
index 0000000..be8572d
--- /dev/null
+++ b/src/packages/ConfigurationBuilders.UserSecrets.nupkg/README.txt
@@ -0,0 +1,41 @@
+########################################################################################################################
+##                                                                                                                    ##
+##                             Microsoft.Configuration.ConfigurationBuilders.UserSecrets                              ##
+##                                                                                                                    ##
+########################################################################################################################
+
+WARNING: Double check config builder attributes in your configuraiton files. Some attributes may have been changed
+         when upgrading this package.
+
+If this is the first time you are installing this configuration builder into your
+project, feel free to click the 'X' on this tab to close and continue on.
+
+However, if you are updating this package from a version earlier than 1.0.2... you may want to double check the
+declarations for your config builders, because we might have lost changes you made to the default declarations
+that were created during the original install.
+
+The upgrade mechanism for nuget is actually just Uninstall/Install, and prior to 1.0.2, this package would delete
+the config builder declaration that it created upon install. Makes sense. But if you made any changes to that
+declaration without changing the name of it, we didn't bother to make note of that. So the 'install' phase of
+updating will declare the default config builder with the default parameters again. (If you did change the name
+to something other than the default - Secrets - then we did not delete your declaration when uninstalling.)
+
+Starting in version 1.0.2, we have a way to stash old declarations aside and restore them upon install. Sorry for the
+inconvenience. There should be no such troubles with future upgrades.
+
+
+########################################################################################################################
+
+
+In addition to the upgrade trouble mentioned above, we have also made changes to the UserSecrets package specifically.
+We no longer create an empty secrets file, nor do we add a link under 'Properties' to the empty secrets file that we
+no longer create. And we do not install any .targets/.props files to magically read $(UserSecretsId) from project
+settings at compile-time.
+
+Why? Because Visual Studio will handle these things for you. Similar to the ASP.Net Core User Secrets experience, VS
+will have a contextual "Manage User Secrets..." option for your Web Forms projects. Using that will install this
+package, create the empty secrets file, and open it for editing. So you will use that menu item instead of seeing
+a project item for secrets.
+
+Also, the first and final word on UserSecretsId is what is set in the builder declaration. No more cumbersome
+attempts at using project properties in configuration at runtime. Now, what you see (in *.config) is what you get. :)
diff --git a/src/packages/packages.csproj b/src/packages/packages.csproj
index e53da29..974f29c 100644
--- a/src/packages/packages.csproj
+++ b/src/packages/packages.csproj
@@ -63,6 +63,12 @@
     <None Include="ConfigurationBuilders.Json.nupkg\tools\Net471\Install.ps1" />
     <None Include="ConfigurationBuilders.Json.nupkg\tools\Net471\Uninstall.ps1" />
   </ItemGroup>
+  <ItemGroup>
+    <Content Include="ConfigurationBuilders.Azure.nupkg\README.txt" />
+    <Content Include="ConfigurationBuilders.Environment.nupkg\README.txt" />
+    <Content Include="ConfigurationBuilders.Json.nupkg\README.txt" />
+    <Content Include="ConfigurationBuilders.UserSecrets.nupkg\README.txt" />
+  </ItemGroup>
   <Import Project="$(MSBuildToolsPath)\Microsoft.CSharp.targets" />
   <Target Name="Build">
     <MSBuild Projects="@(NuGetProject)" Targets="Build" />