diff --git a/Tests/Public/Checkpoint-ZertoVpg.Tests.ps1 b/Tests/Public/Checkpoint-ZertoVpg.Tests.ps1
index 50d2f9d..206bfaa 100644
--- a/Tests/Public/Checkpoint-ZertoVpg.Tests.ps1
+++ b/Tests/Public/Checkpoint-ZertoVpg.Tests.ps1
@@ -9,11 +9,34 @@ Get-Module -Name ZertoApiWrapper | Remove-Module -Force
 Import-Module $moduleFile -Force
 
 Describe $file.BaseName -Tag 'Unit' {
-
+    Mock -ModuleName ZertoApiWrapper -CommandName Invoke-ZertoRestRequest {
+        return "3b687246-ac63-40da-9a59-b99863769eb0.928a122b-1763-4664-ad37-cc00bb883f2f"
+    }
+    Mock -ModuleName ZertoApiWrapper -CommandName get-zertovpg {
+        return @{vpgIdentifier = "dddf2fa8-79e2-4e4f-a83b-f66676afea64"}
+    }
     It "is valid Powershell (Has no script errors)" {
         $contents = Get-Content -Path $file -ErrorAction Stop
         $errors = $null
         $null = [System.Management.Automation.PSParser]::Tokenize($contents, [ref]$errors)
         $errors | Should -HaveCount 0
     }
+
+    it "should return a string" {
+        $results = Checkpoint-ZertoVpg -vpgName "MyVpg" -checkpointName "My Checkpoint Name"
+        $results | should -not -BeNullOrEmpty
+        $results | should -BeOfType "String"
+        $results | should -BeExactly "3b687246-ac63-40da-9a59-b99863769eb0.928a122b-1763-4664-ad37-cc00bb883f2f"
+    }
+
+    it "should require a tag name" {
+        {Checkpoint-ZertoVpg -vpgName "MyVpg" -checkpointName ""} | Should -Throw
+    }
+
+    it "should NOT support '-WhatIf'" {
+        {Checkpoint-ZertoVpg -vpgName "MyVpg" -checkpointName "Checkers" -whatif} | Should -Throw
+    }
+
+    Assert-MockCalled -ModuleName ZertoApiWrapper -CommandName Invoke-ZertoRestRequest
+    Assert-MockCalled -ModuleName ZertoApiWrapper -CommandName Get-ZertoVpg
 }
\ No newline at end of file