diff --git a/InternalsVisibleTo.MSBuild.nuspec b/InternalsVisibleTo.MSBuild.nuspec
index a20c49f..b1163d0 100644
--- a/InternalsVisibleTo.MSBuild.nuspec
+++ b/InternalsVisibleTo.MSBuild.nuspec
@@ -2,7 +2,7 @@
 <package xmlns="http://schemas.microsoft.com/packaging/2010/07/nuspec.xsd">
     <metadata>
         <id>InternalsVisibleTo.MSBuild</id>
-        <version>1.0.5</version>
+        <version>1.1.0</version>
         <description>Enables declaring 'InternalsVisibleTo' items in a .NET project file, rather than declaring them to an AssemblyInfo.cs file.</description>
         <authors>Thomas Levesque</authors>
         <projectUrl>https://github.com/thomaslevesque/InternalsVisibleTo.MSBuild</projectUrl>
diff --git a/README.md b/README.md
index b198949..f7baf9d 100644
--- a/README.md
+++ b/README.md
@@ -4,6 +4,8 @@
 
 Enables declaring `InternalsVisibleTo` items in a .NET project file, rather than declaring them in an AssemblyInfo.cs file.
 
+**IMPORTANT: starting with .NET 5.0, the SDK [already provides support for this](https://github.com/dotnet/sdk/pull/3439). You don't need this package if you're using the .NET 5.0 SDK or later.**
+
 ## How to use
 
 1. Install the `InternalsVisibleTo.MSBuild` NuGet package.
diff --git a/build/InternalsVisibleTo.MSBuild.targets b/build/InternalsVisibleTo.MSBuild.targets
index 8db2c36..c9307c9 100644
--- a/build/InternalsVisibleTo.MSBuild.targets
+++ b/build/InternalsVisibleTo.MSBuild.targets
@@ -2,24 +2,31 @@
 
   <PropertyGroup>
     <MSBuildAllProjects>$(MSBuildAllProjects);$(MSBuildThisFileFullPath)</MSBuildAllProjects>
+    <MSBuild_16_5_0_OrGreater>false</MSBuild_16_5_0_OrGreater>
+    <MSBuild_16_5_0_OrGreater Condition="$([System.Version]::Parse('$(MSBuildVersion)').CompareTo($([System.Version]::Parse('16.5.0')))) &gt;= 0">true</MSBuild_16_5_0_OrGreater>
+    <SdkSupportsInternalsVisibleTo>false</SdkSupportsInternalsVisibleTo>
+    <SdkSupportsInternalsVisibleTo Condition="'$(MSBuild_16_5_0_OrGreater)' == 'true' and $([MSBuild]::VersionGreaterThanOrEquals($(NETCoreSdkVersion), '5.0.0'))">true</SdkSupportsInternalsVisibleTo>
   </PropertyGroup>
 
   <Target Name="AddInternalsVisibleTo" BeforeTargets="BeforeCompile">
 
-    <ItemGroup Condition="@(InternalsVisibleTo->Count()) &gt; 0">
+    <ItemGroup Condition="@(InternalsVisibleTo->Count()) &gt; 0 and '$(SdkSupportsInternalsVisibleTo)' == 'false'">
       <AssemblyAttribute Include="System.Runtime.CompilerServices.InternalsVisibleTo">
         <_Parameter1>%(InternalsVisibleTo.Identity)</_Parameter1>
         <_Parameter1_TypeName>System.String</_Parameter1_TypeName>
       </AssemblyAttribute>
     </ItemGroup>
     
-    <ItemGroup Condition="@(InternalsVisibleToSuffix->Count()) &gt; 0">
+    <ItemGroup Condition="@(InternalsVisibleToSuffix->Count()) &gt; 0 and '$(SdkSupportsInternalsVisibleTo)' == 'false'">
       <AssemblyAttribute Include="System.Runtime.CompilerServices.InternalsVisibleTo">
         <_Parameter1>$(AssemblyName)%(InternalsVisibleToSuffix.Identity)</_Parameter1>
         <_Parameter1_TypeName>System.String</_Parameter1_TypeName>
       </AssemblyAttribute>
     </ItemGroup>
 
+    <Warning Condition="'$(SdkSupportsInternalsVisibleTo)' == 'true'"
+             Text="Starting with version 5.0, the .NET SDK has built-in support for InternalsVisibleTo. The functionality provided by the InternalsVisibleTo.MSBuild package has been disabled to avoid conflicts. You should uninstall this package; note that with the .NET SDK feature, the public key is specified in a separate 'Key' attribute, instead of being appended to the assembly name in the 'Include' attribute." />
+
   </Target>
 
 </Project>