diff --git a/src/ResXManager.View/Behaviors/EntityFilter.cs b/src/ResXManager.View/Behaviors/EntityFilter.cs
index 0e72dc0d..94b13228 100644
--- a/src/ResXManager.View/Behaviors/EntityFilter.cs
+++ b/src/ResXManager.View/Behaviors/EntityFilter.cs
@@ -1,4 +1,4 @@
-namespace ResXManager.View.Behaviors;
+namespace ResXManager.View.Behaviors;
 
 using System;
 using System.Text.RegularExpressions;
@@ -8,6 +8,7 @@
 using Microsoft.Xaml.Behaviors;
 
 using ResXManager.Infrastructure;
+using ResXManager.Model;
 
 using Throttle;
 
@@ -26,21 +27,49 @@ public string? FilterText
     /// </summary>
     public static readonly DependencyProperty FilterTextProperty =
         DependencyProperty.Register(nameof(FilterText), typeof(string), typeof(EntityFilter),
-            new FrameworkPropertyMetadata(null, (sender, _) => ((EntityFilter)sender).FilterText_Changed()));
+            new FrameworkPropertyMetadata(null, (sender, _) => ((EntityFilter)sender).Filter_Changed()));
+
+    public string? ProjectFilter
+    {
+        get => (string)GetValue(ProjectFilterProperty);
+        set => SetValue(ProjectFilterProperty, value);
+    }
+    /// <summary>
+    /// Identifies the <see cref="ProjectFilter"/> dependency property
+    /// </summary>
+    public static readonly DependencyProperty ProjectFilterProperty =
+        DependencyProperty.Register(nameof(ProjectFilter), typeof(string), typeof(EntityFilter),
+            new FrameworkPropertyMetadata(null, (sender, _) => ((EntityFilter)sender).Filter_Changed()));
 
     [Throttled(typeof(Throttle), 300)]
-    private void FilterText_Changed()
+    private void Filter_Changed()
     {
         var listBox = AssociatedObject;
         if (listBox == null)
             return;
 
-        var value = FilterText;
+        var textFilter = BuildTextFilter(FilterText);
+        var projectFilter = ProjectFilter;
 
-        listBox.Items.Filter = BuildFilter(value);
+        if (textFilter == null && projectFilter == null)
+        {
+            listBox.Items.Filter = null;
+            return;
+        }
+
+        listBox.Items.Filter = item =>
+        {
+            if (projectFilter != null && item is ResourceEntity entity && !string.Equals(entity.ProjectName, projectFilter, StringComparison.OrdinalIgnoreCase))
+                return false;
+
+            if (textFilter != null && !textFilter(item))
+                return false;
+
+            return true;
+        };
     }
 
-    public static Predicate<object>? BuildFilter(string? value)
+    public static Predicate<object>? BuildTextFilter(string? value)
     {
         value = value?.Trim();
 
@@ -68,10 +97,13 @@ private void FilterText_Changed()
         return null;
     }
 
+    // Keep for backward compatibility with any external callers
+    public static Predicate<object>? BuildFilter(string? value) => BuildTextFilter(value);
+
     protected override void OnAttached()
     {
         base.OnAttached();
 
-        FilterText_Changed();
+        Filter_Changed();
     }
 }
diff --git a/src/ResXManager.View/Properties/Resources.Designer.cs b/src/ResXManager.View/Properties/Resources.Designer.cs
index 64e4c85e..4ac54305 100644
--- a/src/ResXManager.View/Properties/Resources.Designer.cs
+++ b/src/ResXManager.View/Properties/Resources.Designer.cs
@@ -115,6 +115,24 @@ public static string AllLanguages {
             }
         }
 
+        /// <summary>
+        ///   Looks up a localized string similar to "All Projects"
+        /// </summary>
+        public static string AllProjects {
+            get {
+                return ResourceManager.GetString("AllProjects", resourceCulture) ?? string.Empty;
+            }
+        }
+
+        /// <summary>
+        ///   Looks up a localized string similar to "Filter resource files by project"
+        /// </summary>
+        public static string ProjectFilterToolTip {
+            get {
+                return ResourceManager.GetString("ProjectFilterToolTip", resourceCulture) ?? string.Empty;
+            }
+        }
+
         /// <summary>
         ///   Looks up a localized string similar to "Append the translation prefix to"
         /// </summary>
@@ -1170,6 +1188,14 @@ public enum StringResourceKey
         /// </summary>
         AllLanguages,
         /// <summary>
+        ///   Looks up a localized string similar to All Projects.
+        /// </summary>
+        AllProjects,
+        /// <summary>
+        ///   Looks up a localized string similar to Filter resource files by project.
+        /// </summary>
+        ProjectFilterToolTip,
+        /// <summary>
         ///   Looks up a localized string similar to Append the translation prefix to.
         /// </summary>
         AppendPrefixValueFieldTypeLabel,
diff --git a/src/ResXManager.View/Properties/Resources.resx b/src/ResXManager.View/Properties/Resources.resx
index a558b589..0f6f1c7e 100644
--- a/src/ResXManager.View/Properties/Resources.resx
+++ b/src/ResXManager.View/Properties/Resources.resx
@@ -459,6 +459,12 @@ Your ResXManager team.
   <data name="AllLanguages" xml:space="preserve">
     <value>All languages</value>
   </data>
+  <data name="AllProjects" xml:space="preserve">
+    <value>All Projects</value>
+  </data>
+  <data name="ProjectFilterToolTip" xml:space="preserve">
+    <value>Filter resource files by project</value>
+  </data>
   <data name="AllComments" xml:space="preserve">
     <value>All comments</value>
   </data>
diff --git a/src/ResXManager.View/Visuals/ResourceView.xaml b/src/ResXManager.View/Visuals/ResourceView.xaml
index 87eb3aab..681d8875 100644
--- a/src/ResXManager.View/Visuals/ResourceView.xaml
+++ b/src/ResXManager.View/Visuals/ResourceView.xaml
@@ -89,6 +89,8 @@
       <Grid.RowDefinitions>
         <RowDefinition Height="24" MinHeight="24" />
         <RowDefinition Height="4" />
+        <RowDefinition Height="Auto" />
+        <RowDefinition Height="4" />
         <RowDefinition Height="*" />
       </Grid.RowDefinitions>
       <DockPanel Grid.Row="0">
@@ -113,7 +115,31 @@
         </Border>
       </DockPanel>
 
-      <ListBox x:Name="ListBox" Grid.Row="2"
+      <ComboBox x:Name="ProjectFilterComboBox" Grid.Row="2"
+                ItemsSource="{Binding ProjectNames}"
+                SelectedItem="{Binding SelectedProject}"
+                IsEditable="False"
+                ToolTip="{x:Static properties:Resources.ProjectFilterToolTip}"
+                Style="{DynamicResource {x:Static styles:ResourceKeys.ComboBoxStyle}}">
+        <ComboBox.ItemTemplate>
+          <DataTemplate DataType="{x:Type visuals:ProjectFilterItem}">
+            <TextBlock>
+              <TextBlock.Style>
+                <Style TargetType="TextBlock">
+                  <Setter Property="Text" Value="{Binding ProjectName}" />
+                  <Style.Triggers>
+                    <DataTrigger Binding="{Binding ProjectName}" Value="{x:Null}">
+                      <Setter Property="Text" Value="{x:Static properties:Resources.AllProjects}" />
+                    </DataTrigger>
+                  </Style.Triggers>
+                </Style>
+              </TextBlock.Style>
+            </TextBlock>
+          </DataTemplate>
+        </ComboBox.ItemTemplate>
+      </ComboBox>
+
+      <ListBox x:Name="ListBox" Grid.Row="4"
                ItemsSource="{Binding Source={StaticResource ResourceEntitiesSource}}"
                Padding="5,0" BorderThickness="1" SelectionMode="Extended"
                toms:MultiSelectorExtensions.SelectionBinding="{Binding SelectedEntities}"
@@ -165,7 +191,7 @@
           </ContextMenu>
         </ListBox.ContextMenu>
         <interactions:Interaction.Behaviors>
-          <behaviors:EntityFilter FilterText="{Binding Text, ElementName=EntityFilter}" />
+          <behaviors:EntityFilter FilterText="{Binding Text, ElementName=EntityFilter}" ProjectFilter="{Binding EffectiveProjectFilter}" />
           <behaviors:SelectAllBehavior x:Name="SelectAllBehavior" />
         </interactions:Interaction.Behaviors>
       </ListBox>
diff --git a/src/ResXManager.View/Visuals/ResourceViewModel.cs b/src/ResXManager.View/Visuals/ResourceViewModel.cs
index cdff085c..14bfcbdf 100644
--- a/src/ResXManager.View/Visuals/ResourceViewModel.cs
+++ b/src/ResXManager.View/Visuals/ResourceViewModel.cs
@@ -18,6 +18,8 @@
 
 using DataGridExtensions;
 
+using PropertyChanged;
+
 using ResXManager.Infrastructure;
 using ResXManager.Model;
 using ResXManager.View.ColumnHeaders;
@@ -58,6 +60,7 @@ public ResourceViewModel(ResourceManager resourceManager, IConfiguration configu
         ResourceTableEntries.CollectionChanged += (_, __) => ResourceTableEntries_CollectionChanged();
 
         resourceManager.LanguageChanged += ResourceManager_LanguageChanged;
+        resourceManager.ResourceEntities.CollectionChanged += (_, __) => UpdateProjectNames();
     }
 
     internal event EventHandler<ResourceTableEntryEventArgs>? ClearFiltersRequest;
@@ -70,6 +73,34 @@ public ResourceViewModel(ResourceManager resourceManager, IConfiguration configu
 
     public ObservableCollection<ResourceTableEntry> SelectedTableEntries { get; } = [];
 
+    public ObservableCollection<ProjectFilterItem> ProjectNames { get; } = [];
+
+    private void UpdateProjectNames()
+    {
+        var selectedProjectName = SelectedProject?.ProjectName;
+
+        var names = ResourceManager.ResourceEntities
+            .Select(e => e.ProjectName)
+            .Distinct()
+            .OrderBy(n => n, StringComparer.CurrentCultureIgnoreCase)
+            .ToList();
+
+        ProjectNames.Clear();
+        ProjectNames.Add(ProjectFilterItem.AllProjects);
+        foreach (var name in names)
+            ProjectNames.Add(new ProjectFilterItem(name));
+
+        // Restore selection if the project still exists, otherwise reset to All Projects
+        SelectedProject = (selectedProjectName != null
+            ? ProjectNames.FirstOrDefault(p => p.ProjectName == selectedProjectName)
+            : null) ?? ProjectNames[0];
+    }
+
+    public ProjectFilterItem? SelectedProject { get; set; }
+
+    [DependsOn(nameof(SelectedProject))]
+    public string? EffectiveProjectFilter => SelectedProject?.ProjectName;
+
     public bool IsLoading { get; private set; }
 
     // Do not use CollectionViewSource in XAML, has huge performance impact when there are many items in the list.
@@ -628,3 +659,10 @@ public void Dispose()
         Interlocked.Exchange(ref _loadingCancellationTokenSource, null)?.Dispose();
     }
 }
+
+public sealed class ProjectFilterItem(string? projectName)
+{
+    public static readonly ProjectFilterItem AllProjects = new(null);
+
+    public string? ProjectName { get; } = projectName;
+}