diff --git a/CHANGELOG.md b/CHANGELOG.md
index e007c6fb..e5ebe25f 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -5,6 +5,10 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
 ## [Unreleased]
+### Changed
+- Upgrade MSAL from `4.55.0` to `4.59.1`.
+
+### Added
 - Added the word `Warning` before logging IWA failures so users worry less about IWA issues.
 
 ## [0.8.5] - 2024-03-06
diff --git a/src/AdoPat/AdoPat.csproj b/src/AdoPat/AdoPat.csproj
index 1e0a08ba..a5d21348 100644
--- a/src/AdoPat/AdoPat.csproj
+++ b/src/AdoPat/AdoPat.csproj
@@ -1,4 +1,4 @@
-<Project Sdk="Microsoft.NET.Sdk">
+<Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
     <PackageId>Microsoft.Authentication.AdoPat</PackageId>
@@ -11,7 +11,7 @@
     <AdditionalFiles Include="..\stylecop\stylecop.json" Link="stylecop.json" />
     <Compile Include="..\stylecop\GlobalSuppressions.cs" Link="GlobalSuppressions.cs" />
     <PackageReference Include="Microsoft.Extensions.Logging.Abstractions" Version="3.1.4" />
-    <PackageReference Include="Microsoft.Identity.Client.Extensions.Msal" Version="2.32.0" />
+    <PackageReference Include="Microsoft.Identity.Client.Extensions.Msal" Version="4.59.1" />
     <PackageReference Include="Microsoft.VisualStudio.Services.Client" Version="19.215.0-preview" />
     <PackageReference Include="System.Data.SqlClient" Version="4.8.6" />
   </ItemGroup>
diff --git a/src/MSALWrapper.Benchmark/MSALWrapper.Benchmark.csproj b/src/MSALWrapper.Benchmark/MSALWrapper.Benchmark.csproj
index cbe482c9..2652e4db 100644
--- a/src/MSALWrapper.Benchmark/MSALWrapper.Benchmark.csproj
+++ b/src/MSALWrapper.Benchmark/MSALWrapper.Benchmark.csproj
@@ -21,7 +21,7 @@
     </PropertyGroup>
     <ItemGroup>
         <PackageReference Include="BenchmarkDotNet" Version="0.13.2" />
-        <PackageReference Include="Microsoft.Identity.Client.Broker" Version="4.55.0" />
+        <PackageReference Include="Microsoft.Identity.Client.Broker" Version="4.59.1" />
     </ItemGroup>
     <ItemGroup>
         <ProjectReference Include="..\MSALWrapper\MSALWrapper.csproj" />
@@ -31,7 +31,7 @@
         <!--Windows: Explicitly continue using the net5 version of MSAL since there is no net6 target yet 
          https://github.com/AzureAD/microsoft-authentication-library-for-dotnet/issues/3682-->
         <PackageReference Include="Microsoft.Identity.Client" GeneratePathProperty="true">
-            <Version>4.55.0</Version>
+            <Version>4.59.1</Version>
         </PackageReference>
 
         <Reference Include="Microsoft.Identity.Client">
@@ -41,6 +41,6 @@
     
     <ItemGroup Condition="$([MSBuild]::IsOSPlatform('Windows')) == false">
         <!-- Not Windows: simple package reference -->
-        <PackageReference Include="Microsoft.Identity.Client" Version="4.55.0" />
+        <PackageReference Include="Microsoft.Identity.Client" Version="4.59.1" />
     </ItemGroup>
 </Project>
diff --git a/src/MSALWrapper/MSALWrapper.csproj b/src/MSALWrapper/MSALWrapper.csproj
index acecff24..cc2fed03 100644
--- a/src/MSALWrapper/MSALWrapper.csproj
+++ b/src/MSALWrapper/MSALWrapper.csproj
@@ -1,4 +1,4 @@
-<Project Sdk="Microsoft.NET.Sdk">
+<Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
     <!-- Package Naming, Building, & Versioning -->
@@ -30,10 +30,10 @@
 
   <ItemGroup>
     <PackageReference Include="Microsoft.Extensions.Logging.Abstractions" Version="3.1.4" />
-    <PackageReference Include="Microsoft.Identity.Client.Extensions.Msal" Version="2.32.0" />
+    <PackageReference Include="Microsoft.Identity.Client.Extensions.Msal" Version="4.59.1" />
     <PackageReference Include="Microsoft.IdentityModel.JsonWebTokens" Version="7.5.0" />
-    <PackageReference Include="Microsoft.Identity.Client.Broker" Version="4.55.0" />
-    <PackageReference Include="Microsoft.Identity.Client" Version="4.55.0" />
+    <PackageReference Include="Microsoft.Identity.Client.Broker" Version="4.59.1" />
+    <PackageReference Include="Microsoft.Identity.Client" Version="4.59.1" />
 
   </ItemGroup>