diff --git a/SharepointToolbox.Tests/Services/BulkOperationRunnerTests.cs b/SharepointToolbox.Tests/Services/BulkOperationRunnerTests.cs
new file mode 100644
index 0000000..e510ecd
--- /dev/null
+++ b/SharepointToolbox.Tests/Services/BulkOperationRunnerTests.cs
@@ -0,0 +1,105 @@
+using SharepointToolbox.Core.Models;
+using SharepointToolbox.Services;
+
+namespace SharepointToolbox.Tests.Services;
+
+public class BulkOperationRunnerTests
+{
+    [Fact]
+    public async Task RunAsync_AllSucceed_ReturnsAllSuccess()
+    {
+        var items = new List<string> { "a", "b", "c" };
+        var progress = new Progress<OperationProgress>();
+
+        var summary = await BulkOperationRunner.RunAsync(
+            items,
+            (item, idx, ct) => Task.CompletedTask,
+            progress,
+            CancellationToken.None);
+
+        Assert.Equal(3, summary.TotalCount);
+        Assert.Equal(3, summary.SuccessCount);
+        Assert.Equal(0, summary.FailedCount);
+        Assert.False(summary.HasFailures);
+    }
+
+    [Fact]
+    public async Task RunAsync_SomeItemsFail_ContinuesAndReportsPerItem()
+    {
+        var items = new List<string> { "ok1", "fail", "ok2" };
+        var progress = new Progress<OperationProgress>();
+
+        var summary = await BulkOperationRunner.RunAsync(
+            items,
+            (item, idx, ct) =>
+            {
+                if (item == "fail") throw new InvalidOperationException("Test error");
+                return Task.CompletedTask;
+            },
+            progress,
+            CancellationToken.None);
+
+        Assert.Equal(3, summary.TotalCount);
+        Assert.Equal(2, summary.SuccessCount);
+        Assert.Equal(1, summary.FailedCount);
+        Assert.True(summary.HasFailures);
+        Assert.Contains(summary.FailedItems, r => r.ErrorMessage == "Test error");
+    }
+
+    [Fact]
+    public async Task RunAsync_Cancelled_ThrowsOperationCanceled()
+    {
+        var items = new List<string> { "a", "b", "c" };
+        var cts = new CancellationTokenSource();
+        cts.Cancel();
+        var progress = new Progress<OperationProgress>();
+
+        await Assert.ThrowsAsync<OperationCanceledException>(() =>
+            BulkOperationRunner.RunAsync(
+                items,
+                (item, idx, ct) => Task.CompletedTask,
+                progress,
+                cts.Token));
+    }
+
+    [Fact]
+    public async Task RunAsync_CancelledMidOperation_StopsProcessing()
+    {
+        var items = new List<string> { "a", "b", "c", "d" };
+        var cts = new CancellationTokenSource();
+        var processedCount = 0;
+        var progress = new Progress<OperationProgress>();
+
+        await Assert.ThrowsAsync<OperationCanceledException>(() =>
+            BulkOperationRunner.RunAsync(
+                items,
+                async (item, idx, ct) =>
+                {
+                    Interlocked.Increment(ref processedCount);
+                    if (idx == 1) cts.Cancel(); // cancel after second item
+                    await Task.CompletedTask;
+                },
+                progress,
+                cts.Token));
+
+        Assert.True(processedCount <= 3); // should not process all 4
+    }
+
+    [Fact]
+    public async Task RunAsync_ReportsProgress()
+    {
+        var items = new List<string> { "a", "b" };
+        var progressReports = new List<OperationProgress>();
+        var progress = new Progress<OperationProgress>(p => progressReports.Add(p));
+
+        await BulkOperationRunner.RunAsync(
+            items,
+            (item, idx, ct) => Task.CompletedTask,
+            progress,
+            CancellationToken.None);
+
+        // Progress is async, give it a moment to flush
+        await Task.Delay(100);
+        Assert.True(progressReports.Count >= 2);
+    }
+}
diff --git a/SharepointToolbox.Tests/Services/BulkResultCsvExportServiceTests.cs b/SharepointToolbox.Tests/Services/BulkResultCsvExportServiceTests.cs
new file mode 100644
index 0000000..233953e
--- /dev/null
+++ b/SharepointToolbox.Tests/Services/BulkResultCsvExportServiceTests.cs
@@ -0,0 +1,45 @@
+using SharepointToolbox.Core.Models;
+using SharepointToolbox.Services.Export;
+
+namespace SharepointToolbox.Tests.Services;
+
+public class BulkResultCsvExportServiceTests
+{
+    [Fact]
+    public void BuildFailedItemsCsv_WithFailedItems_IncludesErrorColumn()
+    {
+        var service = new BulkResultCsvExportService();
+        var items = new List<BulkItemResult<BulkMemberRow>>
+        {
+            BulkItemResult<BulkMemberRow>.Failed(
+                new BulkMemberRow { Email = "bad@test.com", GroupName = "G1", GroupUrl = "http://test", Role = "Member" },
+                "User not found"),
+        };
+
+        var csv = service.BuildFailedItemsCsv(items);
+
+        Assert.Contains("Error", csv);
+        Assert.Contains("Timestamp", csv);
+        Assert.Contains("bad@test.com", csv);
+        Assert.Contains("User not found", csv);
+    }
+
+    [Fact]
+    public void BuildFailedItemsCsv_SuccessItems_Excluded()
+    {
+        var service = new BulkResultCsvExportService();
+        var items = new List<BulkItemResult<BulkMemberRow>>
+        {
+            BulkItemResult<BulkMemberRow>.Success(
+                new BulkMemberRow { Email = "ok@test.com", GroupName = "G1", GroupUrl = "http://test", Role = "Member" }),
+            BulkItemResult<BulkMemberRow>.Failed(
+                new BulkMemberRow { Email = "bad@test.com", GroupName = "G1", GroupUrl = "http://test", Role = "Member" },
+                "Error"),
+        };
+
+        var csv = service.BuildFailedItemsCsv(items);
+
+        Assert.DoesNotContain("ok@test.com", csv);
+        Assert.Contains("bad@test.com", csv);
+    }
+}
diff --git a/SharepointToolbox.Tests/Services/CsvValidationServiceTests.cs b/SharepointToolbox.Tests/Services/CsvValidationServiceTests.cs
new file mode 100644
index 0000000..058c095
--- /dev/null
+++ b/SharepointToolbox.Tests/Services/CsvValidationServiceTests.cs
@@ -0,0 +1,36 @@
+using SharepointToolbox.Core.Models;
+
+namespace SharepointToolbox.Tests.Services;
+
+public class CsvValidationServiceTests
+{
+    [Fact(Skip = "Implemented in Plan 04-02")]
+    public void ParseAndValidateMembers_ValidCsv_ReturnsValidRows()
+    {
+    }
+
+    [Fact(Skip = "Implemented in Plan 04-02")]
+    public void ParseAndValidateMembers_InvalidEmail_ReturnsErrors()
+    {
+    }
+
+    [Fact(Skip = "Implemented in Plan 04-02")]
+    public void ParseAndValidateSites_TeamWithoutOwner_ReturnsError()
+    {
+    }
+
+    [Fact(Skip = "Implemented in Plan 04-02")]
+    public void ParseAndValidateFolders_ValidCsv_ReturnsValidRows()
+    {
+    }
+
+    [Fact(Skip = "Implemented in Plan 04-02")]
+    public void ParseAndValidate_BomDetection_WorksWithAndWithoutBom()
+    {
+    }
+
+    [Fact(Skip = "Implemented in Plan 04-02")]
+    public void ParseAndValidate_SemicolonDelimiter_DetectedAutomatically()
+    {
+    }
+}
diff --git a/SharepointToolbox.Tests/Services/TemplateRepositoryTests.cs b/SharepointToolbox.Tests/Services/TemplateRepositoryTests.cs
new file mode 100644
index 0000000..3150383
--- /dev/null
+++ b/SharepointToolbox.Tests/Services/TemplateRepositoryTests.cs
@@ -0,0 +1,26 @@
+using SharepointToolbox.Core.Models;
+
+namespace SharepointToolbox.Tests.Services;
+
+public class TemplateRepositoryTests
+{
+    [Fact(Skip = "Implemented in Plan 04-02")]
+    public void SaveAndLoad_RoundTrips_Correctly()
+    {
+    }
+
+    [Fact(Skip = "Implemented in Plan 04-02")]
+    public void GetAll_ReturnsAllSavedTemplates()
+    {
+    }
+
+    [Fact(Skip = "Implemented in Plan 04-02")]
+    public void Delete_RemovesTemplate()
+    {
+    }
+
+    [Fact(Skip = "Implemented in Plan 04-02")]
+    public void Rename_UpdatesTemplateName()
+    {
+    }
+}
diff --git a/SharepointToolbox.Tests/SharepointToolbox.Tests.csproj b/SharepointToolbox.Tests/SharepointToolbox.Tests.csproj
index 069a016..500ab71 100644
--- a/SharepointToolbox.Tests/SharepointToolbox.Tests.csproj
+++ b/SharepointToolbox.Tests/SharepointToolbox.Tests.csproj
@@ -10,6 +10,7 @@
 
   <ItemGroup>
     <PackageReference Include="coverlet.collector" Version="6.0.4" />
+    <PackageReference Include="CsvHelper" Version="33.1.0" />
     <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.14.1" />
     <PackageReference Include="Moq" Version="4.20.72" />
     <PackageReference Include="xunit" Version="2.9.3" />
diff --git a/SharepointToolbox/Core/Models/BulkMemberRow.cs b/SharepointToolbox/Core/Models/BulkMemberRow.cs
new file mode 100644
index 0000000..6956015
--- /dev/null
+++ b/SharepointToolbox/Core/Models/BulkMemberRow.cs
@@ -0,0 +1,18 @@
+using CsvHelper.Configuration.Attributes;
+
+namespace SharepointToolbox.Core.Models;
+
+public class BulkMemberRow
+{
+    [Name("GroupName")]
+    public string GroupName { get; set; } = string.Empty;
+
+    [Name("GroupUrl")]
+    public string GroupUrl { get; set; } = string.Empty;
+
+    [Name("Email")]
+    public string Email { get; set; } = string.Empty;
+
+    [Name("Role")]
+    public string Role { get; set; } = string.Empty; // "Member" or "Owner"
+}
diff --git a/SharepointToolbox/Core/Models/BulkOperationResult.cs b/SharepointToolbox/Core/Models/BulkOperationResult.cs
new file mode 100644
index 0000000..e8b430f
--- /dev/null
+++ b/SharepointToolbox/Core/Models/BulkOperationResult.cs
@@ -0,0 +1,35 @@
+namespace SharepointToolbox.Core.Models;
+
+public class BulkItemResult<T>
+{
+    public T Item { get; }
+    public bool IsSuccess { get; }
+    public string? ErrorMessage { get; }
+    public DateTime Timestamp { get; }
+
+    private BulkItemResult(T item, bool success, string? error)
+    {
+        Item = item;
+        IsSuccess = success;
+        ErrorMessage = error;
+        Timestamp = DateTime.UtcNow;
+    }
+
+    public static BulkItemResult<T> Success(T item) => new(item, true, null);
+    public static BulkItemResult<T> Failed(T item, string error) => new(item, false, error);
+}
+
+public class BulkOperationSummary<T>
+{
+    public IReadOnlyList<BulkItemResult<T>> Results { get; }
+    public int TotalCount => Results.Count;
+    public int SuccessCount => Results.Count(r => r.IsSuccess);
+    public int FailedCount => Results.Count(r => !r.IsSuccess);
+    public bool HasFailures => FailedCount > 0;
+    public IReadOnlyList<BulkItemResult<T>> FailedItems => Results.Where(r => !r.IsSuccess).ToList();
+
+    public BulkOperationSummary(IReadOnlyList<BulkItemResult<T>> results)
+    {
+        Results = results;
+    }
+}
diff --git a/SharepointToolbox/Core/Models/BulkSiteRow.cs b/SharepointToolbox/Core/Models/BulkSiteRow.cs
new file mode 100644
index 0000000..4110f0f
--- /dev/null
+++ b/SharepointToolbox/Core/Models/BulkSiteRow.cs
@@ -0,0 +1,24 @@
+using CsvHelper.Configuration.Attributes;
+
+namespace SharepointToolbox.Core.Models;
+
+public class BulkSiteRow
+{
+    [Name("Name")]
+    public string Name { get; set; } = string.Empty;
+
+    [Name("Alias")]
+    public string Alias { get; set; } = string.Empty;
+
+    [Name("Type")]
+    public string Type { get; set; } = string.Empty; // "Team" or "Communication"
+
+    [Name("Template")]
+    public string Template { get; set; } = string.Empty;
+
+    [Name("Owners")]
+    public string Owners { get; set; } = string.Empty; // comma-separated emails
+
+    [Name("Members")]
+    public string Members { get; set; } = string.Empty; // comma-separated emails
+}
diff --git a/SharepointToolbox/Core/Models/ConflictPolicy.cs b/SharepointToolbox/Core/Models/ConflictPolicy.cs
new file mode 100644
index 0000000..f2ccf4d
--- /dev/null
+++ b/SharepointToolbox/Core/Models/ConflictPolicy.cs
@@ -0,0 +1,8 @@
+namespace SharepointToolbox.Core.Models;
+
+public enum ConflictPolicy
+{
+    Skip,
+    Overwrite,
+    Rename
+}
diff --git a/SharepointToolbox/Core/Models/CsvValidationRow.cs b/SharepointToolbox/Core/Models/CsvValidationRow.cs
new file mode 100644
index 0000000..42f03b9
--- /dev/null
+++ b/SharepointToolbox/Core/Models/CsvValidationRow.cs
@@ -0,0 +1,25 @@
+namespace SharepointToolbox.Core.Models;
+
+public class CsvValidationRow<T>
+{
+    public T? Record { get; }
+    public bool IsValid => Errors.Count == 0;
+    public List<string> Errors { get; }
+    public string? RawRecord { get; }
+
+    public CsvValidationRow(T record, List<string> errors)
+    {
+        Record = record;
+        Errors = errors;
+    }
+
+    private CsvValidationRow(string rawRecord, string parseError)
+    {
+        Record = default;
+        RawRecord = rawRecord;
+        Errors = new List<string> { parseError };
+    }
+
+    public static CsvValidationRow<T> ParseError(string? rawRecord, string error)
+        => new(rawRecord ?? string.Empty, error);
+}
diff --git a/SharepointToolbox/Core/Models/FolderStructureRow.cs b/SharepointToolbox/Core/Models/FolderStructureRow.cs
new file mode 100644
index 0000000..147dc11
--- /dev/null
+++ b/SharepointToolbox/Core/Models/FolderStructureRow.cs
@@ -0,0 +1,28 @@
+using CsvHelper.Configuration.Attributes;
+
+namespace SharepointToolbox.Core.Models;
+
+public class FolderStructureRow
+{
+    [Name("Level1")]
+    public string Level1 { get; set; } = string.Empty;
+
+    [Name("Level2")]
+    public string Level2 { get; set; } = string.Empty;
+
+    [Name("Level3")]
+    public string Level3 { get; set; } = string.Empty;
+
+    [Name("Level4")]
+    public string Level4 { get; set; } = string.Empty;
+
+    /// <summary>
+    /// Builds the folder path from non-empty level values (e.g. "Admin/HR/Contracts").
+    /// </summary>
+    public string BuildPath()
+    {
+        var parts = new[] { Level1, Level2, Level3, Level4 }
+            .Where(s => !string.IsNullOrWhiteSpace(s));
+        return string.Join("/", parts);
+    }
+}
diff --git a/SharepointToolbox/Core/Models/SiteTemplate.cs b/SharepointToolbox/Core/Models/SiteTemplate.cs
new file mode 100644
index 0000000..9e3e16f
--- /dev/null
+++ b/SharepointToolbox/Core/Models/SiteTemplate.cs
@@ -0,0 +1,27 @@
+namespace SharepointToolbox.Core.Models;
+
+public class SiteTemplate
+{
+    public string Id { get; set; } = Guid.NewGuid().ToString();
+    public string Name { get; set; } = string.Empty;
+    public string SourceUrl { get; set; } = string.Empty;
+    public DateTime CapturedAt { get; set; }
+    public string SiteType { get; set; } = string.Empty; // "Team" or "Communication"
+    public SiteTemplateOptions Options { get; set; } = new();
+    public TemplateSettings? Settings { get; set; }
+    public TemplateLogo? Logo { get; set; }
+    public List<TemplateLibraryInfo> Libraries { get; set; } = new();
+    public List<TemplatePermissionGroup> PermissionGroups { get; set; } = new();
+}
+
+public class TemplateSettings
+{
+    public string Title { get; set; } = string.Empty;
+    public string Description { get; set; } = string.Empty;
+    public int Language { get; set; }
+}
+
+public class TemplateLogo
+{
+    public string LogoUrl { get; set; } = string.Empty;
+}
diff --git a/SharepointToolbox/Core/Models/SiteTemplateOptions.cs b/SharepointToolbox/Core/Models/SiteTemplateOptions.cs
new file mode 100644
index 0000000..dbc1eca
--- /dev/null
+++ b/SharepointToolbox/Core/Models/SiteTemplateOptions.cs
@@ -0,0 +1,10 @@
+namespace SharepointToolbox.Core.Models;
+
+public class SiteTemplateOptions
+{
+    public bool CaptureLibraries { get; set; } = true;
+    public bool CaptureFolders { get; set; } = true;
+    public bool CapturePermissionGroups { get; set; } = true;
+    public bool CaptureLogo { get; set; } = true;
+    public bool CaptureSettings { get; set; } = true;
+}
diff --git a/SharepointToolbox/Core/Models/TemplateFolderInfo.cs b/SharepointToolbox/Core/Models/TemplateFolderInfo.cs
new file mode 100644
index 0000000..235be87
--- /dev/null
+++ b/SharepointToolbox/Core/Models/TemplateFolderInfo.cs
@@ -0,0 +1,8 @@
+namespace SharepointToolbox.Core.Models;
+
+public class TemplateFolderInfo
+{
+    public string Name { get; set; } = string.Empty;
+    public string RelativePath { get; set; } = string.Empty;
+    public List<TemplateFolderInfo> Children { get; set; } = new();
+}
diff --git a/SharepointToolbox/Core/Models/TemplateLibraryInfo.cs b/SharepointToolbox/Core/Models/TemplateLibraryInfo.cs
new file mode 100644
index 0000000..503e245
--- /dev/null
+++ b/SharepointToolbox/Core/Models/TemplateLibraryInfo.cs
@@ -0,0 +1,9 @@
+namespace SharepointToolbox.Core.Models;
+
+public class TemplateLibraryInfo
+{
+    public string Name { get; set; } = string.Empty;
+    public string BaseType { get; set; } = string.Empty; // "DocumentLibrary", "GenericList"
+    public int BaseTemplate { get; set; }
+    public List<TemplateFolderInfo> Folders { get; set; } = new();
+}
diff --git a/SharepointToolbox/Core/Models/TemplatePermissionGroup.cs b/SharepointToolbox/Core/Models/TemplatePermissionGroup.cs
new file mode 100644
index 0000000..94fca80
--- /dev/null
+++ b/SharepointToolbox/Core/Models/TemplatePermissionGroup.cs
@@ -0,0 +1,8 @@
+namespace SharepointToolbox.Core.Models;
+
+public class TemplatePermissionGroup
+{
+    public string Name { get; set; } = string.Empty;
+    public string Description { get; set; } = string.Empty;
+    public List<string> RoleDefinitions { get; set; } = new(); // e.g. "Full Control", "Contribute"
+}
diff --git a/SharepointToolbox/Core/Models/TransferJob.cs b/SharepointToolbox/Core/Models/TransferJob.cs
new file mode 100644
index 0000000..be9d5b8
--- /dev/null
+++ b/SharepointToolbox/Core/Models/TransferJob.cs
@@ -0,0 +1,13 @@
+namespace SharepointToolbox.Core.Models;
+
+public class TransferJob
+{
+    public string SourceSiteUrl { get; set; } = string.Empty;
+    public string SourceLibrary { get; set; } = string.Empty;
+    public string SourceFolderPath { get; set; } = string.Empty; // relative within library
+    public string DestinationSiteUrl { get; set; } = string.Empty;
+    public string DestinationLibrary { get; set; } = string.Empty;
+    public string DestinationFolderPath { get; set; } = string.Empty;
+    public TransferMode Mode { get; set; } = TransferMode.Copy;
+    public ConflictPolicy ConflictPolicy { get; set; } = ConflictPolicy.Skip;
+}
diff --git a/SharepointToolbox/Core/Models/TransferMode.cs b/SharepointToolbox/Core/Models/TransferMode.cs
new file mode 100644
index 0000000..56bfaa4
--- /dev/null
+++ b/SharepointToolbox/Core/Models/TransferMode.cs
@@ -0,0 +1,7 @@
+namespace SharepointToolbox.Core.Models;
+
+public enum TransferMode
+{
+    Copy,
+    Move
+}
diff --git a/SharepointToolbox/Services/BulkOperationRunner.cs b/SharepointToolbox/Services/BulkOperationRunner.cs
new file mode 100644
index 0000000..3155a0e
--- /dev/null
+++ b/SharepointToolbox/Services/BulkOperationRunner.cs
@@ -0,0 +1,36 @@
+using SharepointToolbox.Core.Models;
+
+namespace SharepointToolbox.Services;
+
+public static class BulkOperationRunner
+{
+    /// <summary>
+    /// Runs a bulk operation with continue-on-error semantics, per-item result tracking,
+    /// and cancellation support. OperationCanceledException propagates immediately.
+    /// </summary>
+    public static async Task<BulkOperationSummary<TItem>> RunAsync<TItem>(
+        IReadOnlyList<TItem> items,
+        Func<TItem, int, CancellationToken, Task> processItem,
+        IProgress<OperationProgress> progress,
+        CancellationToken ct)
+    {
+        var results = new List<BulkItemResult<TItem>>();
+        for (int i = 0; i < items.Count; i++)
+        {
+            ct.ThrowIfCancellationRequested();
+            progress.Report(new OperationProgress(i + 1, items.Count, $"Processing {i + 1}/{items.Count}..."));
+            try
+            {
+                await processItem(items[i], i, ct);
+                results.Add(BulkItemResult<TItem>.Success(items[i]));
+            }
+            catch (OperationCanceledException) { throw; }
+            catch (Exception ex)
+            {
+                results.Add(BulkItemResult<TItem>.Failed(items[i], ex.Message));
+            }
+        }
+        progress.Report(new OperationProgress(items.Count, items.Count, "Complete."));
+        return new BulkOperationSummary<TItem>(results);
+    }
+}
diff --git a/SharepointToolbox/Services/Export/BulkResultCsvExportService.cs b/SharepointToolbox/Services/Export/BulkResultCsvExportService.cs
new file mode 100644
index 0000000..58498f7
--- /dev/null
+++ b/SharepointToolbox/Services/Export/BulkResultCsvExportService.cs
@@ -0,0 +1,40 @@
+using System.Globalization;
+using System.IO;
+using System.Text;
+using CsvHelper;
+using SharepointToolbox.Core.Models;
+
+namespace SharepointToolbox.Services.Export;
+
+public class BulkResultCsvExportService
+{
+    public string BuildFailedItemsCsv<T>(IReadOnlyList<BulkItemResult<T>> failedItems)
+    {
+        using var writer = new StringWriter();
+        using var csv = new CsvWriter(writer, CultureInfo.InvariantCulture);
+
+        csv.WriteHeader<T>();
+        csv.WriteField("Error");
+        csv.WriteField("Timestamp");
+        csv.NextRecord();
+
+        foreach (var item in failedItems.Where(r => !r.IsSuccess))
+        {
+            csv.WriteRecord(item.Item);
+            csv.WriteField(item.ErrorMessage);
+            csv.WriteField(item.Timestamp.ToString("o"));
+            csv.NextRecord();
+        }
+
+        return writer.ToString();
+    }
+
+    public async Task WriteFailedItemsCsvAsync<T>(
+        IReadOnlyList<BulkItemResult<T>> failedItems,
+        string filePath,
+        CancellationToken ct)
+    {
+        var content = BuildFailedItemsCsv(failedItems);
+        await System.IO.File.WriteAllTextAsync(filePath, content, new UTF8Encoding(true), ct);
+    }
+}
diff --git a/SharepointToolbox/Services/IBulkMemberService.cs b/SharepointToolbox/Services/IBulkMemberService.cs
new file mode 100644
index 0000000..77c6b23
--- /dev/null
+++ b/SharepointToolbox/Services/IBulkMemberService.cs
@@ -0,0 +1,14 @@
+using Microsoft.SharePoint.Client;
+using SharepointToolbox.Core.Models;
+
+namespace SharepointToolbox.Services;
+
+public interface IBulkMemberService
+{
+    Task<BulkOperationSummary<BulkMemberRow>> AddMembersAsync(
+        ClientContext ctx,
+        string clientId,
+        IReadOnlyList<BulkMemberRow> rows,
+        IProgress<OperationProgress> progress,
+        CancellationToken ct);
+}
diff --git a/SharepointToolbox/Services/IBulkSiteService.cs b/SharepointToolbox/Services/IBulkSiteService.cs
new file mode 100644
index 0000000..803fcd8
--- /dev/null
+++ b/SharepointToolbox/Services/IBulkSiteService.cs
@@ -0,0 +1,13 @@
+using Microsoft.SharePoint.Client;
+using SharepointToolbox.Core.Models;
+
+namespace SharepointToolbox.Services;
+
+public interface IBulkSiteService
+{
+    Task<BulkOperationSummary<BulkSiteRow>> CreateSitesAsync(
+        ClientContext adminCtx,
+        IReadOnlyList<BulkSiteRow> rows,
+        IProgress<OperationProgress> progress,
+        CancellationToken ct);
+}
diff --git a/SharepointToolbox/Services/ICsvValidationService.cs b/SharepointToolbox/Services/ICsvValidationService.cs
new file mode 100644
index 0000000..d895f9f
--- /dev/null
+++ b/SharepointToolbox/Services/ICsvValidationService.cs
@@ -0,0 +1,12 @@
+using System.IO;
+using SharepointToolbox.Core.Models;
+
+namespace SharepointToolbox.Services;
+
+public interface ICsvValidationService
+{
+    List<CsvValidationRow<T>> ParseAndValidate<T>(Stream csvStream) where T : class;
+    List<CsvValidationRow<BulkMemberRow>> ParseAndValidateMembers(Stream csvStream);
+    List<CsvValidationRow<BulkSiteRow>> ParseAndValidateSites(Stream csvStream);
+    List<CsvValidationRow<FolderStructureRow>> ParseAndValidateFolders(Stream csvStream);
+}
diff --git a/SharepointToolbox/Services/IFileTransferService.cs b/SharepointToolbox/Services/IFileTransferService.cs
new file mode 100644
index 0000000..50306dd
--- /dev/null
+++ b/SharepointToolbox/Services/IFileTransferService.cs
@@ -0,0 +1,18 @@
+using Microsoft.SharePoint.Client;
+using SharepointToolbox.Core.Models;
+
+namespace SharepointToolbox.Services;
+
+public interface IFileTransferService
+{
+    /// <summary>
+    /// Transfers files/folders from source to destination.
+    /// Returns per-item results (file paths as string items).
+    /// </summary>
+    Task<BulkOperationSummary<string>> TransferAsync(
+        ClientContext sourceCtx,
+        ClientContext destCtx,
+        TransferJob job,
+        IProgress<OperationProgress> progress,
+        CancellationToken ct);
+}
diff --git a/SharepointToolbox/Services/IFolderStructureService.cs b/SharepointToolbox/Services/IFolderStructureService.cs
new file mode 100644
index 0000000..b931e6f
--- /dev/null
+++ b/SharepointToolbox/Services/IFolderStructureService.cs
@@ -0,0 +1,14 @@
+using Microsoft.SharePoint.Client;
+using SharepointToolbox.Core.Models;
+
+namespace SharepointToolbox.Services;
+
+public interface IFolderStructureService
+{
+    Task<BulkOperationSummary<string>> CreateFoldersAsync(
+        ClientContext ctx,
+        string libraryTitle,
+        IReadOnlyList<FolderStructureRow> rows,
+        IProgress<OperationProgress> progress,
+        CancellationToken ct);
+}
diff --git a/SharepointToolbox/Services/ITemplateService.cs b/SharepointToolbox/Services/ITemplateService.cs
new file mode 100644
index 0000000..43492b3
--- /dev/null
+++ b/SharepointToolbox/Services/ITemplateService.cs
@@ -0,0 +1,22 @@
+using Microsoft.SharePoint.Client;
+using SharepointToolbox.Core.Models;
+using ModelSiteTemplate = SharepointToolbox.Core.Models.SiteTemplate;
+
+namespace SharepointToolbox.Services;
+
+public interface ITemplateService
+{
+    Task<ModelSiteTemplate> CaptureTemplateAsync(
+        ClientContext ctx,
+        SiteTemplateOptions options,
+        IProgress<OperationProgress> progress,
+        CancellationToken ct);
+
+    Task<string> ApplyTemplateAsync(
+        ClientContext adminCtx,
+        ModelSiteTemplate template,
+        string newSiteTitle,
+        string newSiteAlias,
+        IProgress<OperationProgress> progress,
+        CancellationToken ct);
+}
diff --git a/SharepointToolbox/SharepointToolbox.csproj b/SharepointToolbox/SharepointToolbox.csproj
index 24a4c99..c635ea4 100644
--- a/SharepointToolbox/SharepointToolbox.csproj
+++ b/SharepointToolbox/SharepointToolbox.csproj
@@ -27,7 +27,9 @@
 
   <ItemGroup>
     <PackageReference Include="CommunityToolkit.Mvvm" Version="8.4.2" />
+    <PackageReference Include="CsvHelper" Version="33.1.0" />
     <PackageReference Include="Microsoft.Extensions.Hosting" Version="10.0.0" />
+    <PackageReference Include="Microsoft.Graph" Version="5.74.0" />
     <PackageReference Include="Microsoft.Identity.Client" Version="4.83.3" />
     <PackageReference Include="Microsoft.Identity.Client.Broker" Version="4.82.1" />
     <PackageReference Include="Microsoft.Identity.Client.Extensions.Msal" Version="4.83.3" />