diff --git a/src/Hl7.Fhir.Shims.Base/Specification/Terminology/LocalTerminologyService.cs b/src/Hl7.Fhir.Shims.Base/Specification/Terminology/LocalTerminologyService.cs
index 1ec670d688..f0c8d0e266 100644
--- a/src/Hl7.Fhir.Shims.Base/Specification/Terminology/LocalTerminologyService.cs
+++ b/src/Hl7.Fhir.Shims.Base/Specification/Terminology/LocalTerminologyService.cs
@@ -137,7 +137,7 @@ private async Task<ValueSet> getExpandedValueSet(ValueSet vs, string operation)
         {
             // Unprocessable entity
             throw new FhirOperationException(
-                $"Operation {operation} failed: creating the required expansion failed mith message \"{e.Message}\".",
+                $"Operation {operation} failed: creating the required expansion failed with message \"{e.Message}\".",
                 (HttpStatusCode)422);
         }