diff --git a/ZertoApiWrapper/Public/Get-ZertoPeerSite.ps1 b/ZertoApiWrapper/Public/Get-ZertoPeerSite.ps1
index 8f64673..cb86c53 100644
--- a/ZertoApiWrapper/Public/Get-ZertoPeerSite.ps1
+++ b/ZertoApiWrapper/Public/Get-ZertoPeerSite.ps1
@@ -22,6 +22,7 @@ function Get-ZertoPeerSite {
             ParameterSetName = "filter",
             HelpMessage = "The name of a peer site for which information is to be returned. The name is case-sensitive."
         )]
+        [ValidateNotNullOrEmpty()]
         [string]$peerName,
         [Parameter (
             ParameterSetName = "filter",