diff --git a/Rdmp.Core/CohortCommitting/Pipeline/CohortHoldoutLookupRequest.cs b/Rdmp.Core/CohortCommitting/Pipeline/CohortHoldoutLookupRequest.cs
index c47be5fe97..4c0573f569 100644
--- a/Rdmp.Core/CohortCommitting/Pipeline/CohortHoldoutLookupRequest.cs
+++ b/Rdmp.Core/CohortCommitting/Pipeline/CohortHoldoutLookupRequest.cs
@@ -27,12 +27,14 @@ public sealed class CohortHoldoutLookupRequest : PipelineUseCase, ICanBeSummaris
 
     public string DescriptionForAuditLog { get; set; }
 
+    public string WhereQuery { get; set; }
+
     public string Name { get; set; }
 
     public DateTime MinDate { get; set; }
     public DateTime MaxDate { get; set; }
     public string DateColumnName { get; set; }
-    public CohortHoldoutLookupRequest(CohortIdentificationConfiguration cic, string name, int count, bool isPercent, string descriptionForAuditLog,string minDate=null,string maxDate=null,string dateColumnName=null)
+    public CohortHoldoutLookupRequest(CohortIdentificationConfiguration cic, string name, int count, bool isPercent, string descriptionForAuditLog,string whereQuery,string minDate=null,string maxDate=null,string dateColumnName=null)
     {
         CIC = cic;
         Name = name;
@@ -46,6 +48,7 @@ public CohortHoldoutLookupRequest(CohortIdentificationConfiguration cic, string
         DateTime.TryParseExact(maxDate, "DD/MM/YYYY", new CultureInfo("en-GB"), DateTimeStyles.None, out _MaxDate);
         MinDate = _MinDate;
         DateColumnName = dateColumnName;
+        WhereQuery = whereQuery;
         AddInitializationObject(this);
     }
         public string GetSummary(bool includeName, bool includeId)
diff --git a/Rdmp.Core/CommandExecution/BasicActivateItems.cs b/Rdmp.Core/CommandExecution/BasicActivateItems.cs
index cc1734c05f..7e012f057c 100644
--- a/Rdmp.Core/CommandExecution/BasicActivateItems.cs
+++ b/Rdmp.Core/CommandExecution/BasicActivateItems.cs
@@ -687,7 +687,7 @@ public virtual CohortHoldoutLookupRequest GetCohortHoldoutLookupRequest(External
         else
             throw new Exception("User chose not to enter a version number and none was provided");
 
-        return new CohortHoldoutLookupRequest(cic, "empty", 1,false,"");
+        return new CohortHoldoutLookupRequest(cic, "empty", 1,false,"","");
     }
 
     /// <inheritdoc/>
diff --git a/Rdmp.UI/CohortUI/CreateHoldoutLookup/CreateHoldoutLookupUI.cs b/Rdmp.UI/CohortUI/CreateHoldoutLookup/CreateHoldoutLookupUI.cs
index 0ce1ec1468..3435797a36 100644
--- a/Rdmp.UI/CohortUI/CreateHoldoutLookup/CreateHoldoutLookupUI.cs
+++ b/Rdmp.UI/CohortUI/CreateHoldoutLookup/CreateHoldoutLookupUI.cs
@@ -89,7 +89,8 @@ private void btnOk_Click(object sender, EventArgs e)
         string minDate = textBox2.Text;
         string maxDate = textBox3.Text;
         string dateColumnName = textBox4.Text;
-        Result = new CohortHoldoutLookupRequest(_cic, name, Decimal.ToInt32(numericUpDown1.Value), comboBox1.Text == "%", "", minDate, maxDate, dateColumnName);
+        string whereQuery = textBox1.Text;
+        Result = new CohortHoldoutLookupRequest(_cic, name, Decimal.ToInt32(numericUpDown1.Value), comboBox1.Text == "%", "", whereQuery, minDate, maxDate, dateColumnName);
         //see if it is passing checks
         var notifier = new ToMemoryCheckNotifier();
         //Result.Check(notifier);