diff --git a/ChangeLog.md b/ChangeLog.md
index 26f4e63410..6171a20476 100644
--- a/ChangeLog.md
+++ b/ChangeLog.md
@@ -33,6 +33,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - Fix code fix for CS0164 ([#1031](https://github.com/JosefPihrt/Roslynator/pull/1031)).
 - Do not report `System.Windows.DependencyPropertyChangedEventArgs` as unused parameter ([RCS1163](https://github.com/JosefPihrt/Roslynator/blob/main/docs/analyzers/RCS1163.md)) ([#1068](https://github.com/JosefPihrt/Roslynator/pull/1068)).
 - Fix ([RCS1032](https://github.com/JosefPihrt/Roslynator/blob/main/docs/analyzers/RCS1032.md)) ([#1064](https://github.com/JosefPihrt/Roslynator/pull/1064)).
+- Update processing of .globalconfig file to prioritize file-specific diagnostic severities over global diagnostic severities. [#1066](https://github.com/JosefPihrt/Roslynator/pull/1066/files)
 
 ## [4.2.0] - 2022-11-27
 
diff --git a/src/Core/Extensions/DiagnosticsExtensions.cs b/src/Core/Extensions/DiagnosticsExtensions.cs
index 2809cd6540..51ba37c4d3 100644
--- a/src/Core/Extensions/DiagnosticsExtensions.cs
+++ b/src/Core/Extensions/DiagnosticsExtensions.cs
@@ -551,15 +551,12 @@ internal static bool IsEffective(
         CompilationOptions compilationOptions,
         CancellationToken cancellationToken = default)
     {
-        var reportDiagnostic = Microsoft.CodeAnalysis.ReportDiagnostic.Default;
-
         SyntaxTreeOptionsProvider provider = compilationOptions.SyntaxTreeOptionsProvider;
 
-        if (provider is not null
-            && !provider.TryGetGlobalDiagnosticValue(descriptor.Id, cancellationToken, out reportDiagnostic)
-            && !provider.TryGetDiagnosticValue(syntaxTree, descriptor.Id, cancellationToken, out reportDiagnostic))
+        if (provider?.TryGetDiagnosticValue(syntaxTree, descriptor.Id, cancellationToken, out ReportDiagnostic reportDiagnostic) != true
+            && !compilationOptions.SpecificDiagnosticOptions.TryGetValue(descriptor.Id, out reportDiagnostic))
         {
-            reportDiagnostic = compilationOptions.SpecificDiagnosticOptions.GetValueOrDefault(descriptor.Id);
+            provider?.TryGetGlobalDiagnosticValue(descriptor.Id, cancellationToken, out reportDiagnostic);
         }
 
         return reportDiagnostic switch
@@ -577,19 +574,16 @@ internal static ReportDiagnostic GetEffectiveSeverity(
         CancellationToken cancellationToken = default)
     {
         SyntaxTreeOptionsProvider provider = compilationOptions.SyntaxTreeOptionsProvider;
-
-        if (provider is not null)
-        {
-            if (provider.TryGetGlobalDiagnosticValue(descriptor.Id, cancellationToken, out ReportDiagnostic globalReportDiagnostic))
-                return globalReportDiagnostic;
-
-            if (provider.TryGetDiagnosticValue(syntaxTree, descriptor.Id, cancellationToken, out ReportDiagnostic treeReportDiagnostic))
-                return treeReportDiagnostic;
-        }
-
+        
+        if (provider?.TryGetDiagnosticValue(syntaxTree, descriptor.Id, cancellationToken, out ReportDiagnostic treeReportDiagnostic) == true)
+            return treeReportDiagnostic;
+        
         if (compilationOptions.SpecificDiagnosticOptions.TryGetValue(descriptor.Id, out ReportDiagnostic reportDiagnostic))
             return reportDiagnostic;
 
+        if (provider?.TryGetGlobalDiagnosticValue(descriptor.Id, cancellationToken, out ReportDiagnostic globalReportDiagnostic) == true)
+            return globalReportDiagnostic;
+
         return (descriptor.IsEnabledByDefault)
             ? descriptor.DefaultSeverity.ToReportDiagnostic()
             : Microsoft.CodeAnalysis.ReportDiagnostic.Suppress;