diff --git a/Src/java/cql-to-elm/src/main/java/org/cqframework/cql/cql2elm/SystemMethodResolver.java b/Src/java/cql-to-elm/src/main/java/org/cqframework/cql/cql2elm/SystemMethodResolver.java
index fd5383416..b8a2c31f2 100644
--- a/Src/java/cql-to-elm/src/main/java/org/cqframework/cql/cql2elm/SystemMethodResolver.java
+++ b/Src/java/cql-to-elm/src/main/java/org/cqframework/cql/cql2elm/SystemMethodResolver.java
@@ -550,6 +550,8 @@ public Expression resolveMethod(
             }
             case "truncate":
                 return builder.resolveFunction(null, "Truncate", getParams(target, ctx));
+            case "union":
+                return builder.resolveFunction(null, "Union", getParams(target, ctx));
             case "upper":
                 return builder.resolveFunction(null, "Upper", getParams(target, ctx));
             case "where": {
diff --git a/Src/java/engine-fhir/src/test/java/org/hl7/fhirpath/CQLOperationsR4Test.java b/Src/java/engine-fhir/src/test/java/org/hl7/fhirpath/CQLOperationsR4Test.java
index 5afe57d7d..de0b95721 100644
--- a/Src/java/engine-fhir/src/test/java/org/hl7/fhirpath/CQLOperationsR4Test.java
+++ b/Src/java/engine-fhir/src/test/java/org/hl7/fhirpath/CQLOperationsR4Test.java
@@ -210,9 +210,6 @@ public static Object[][] dataMethod() {
             "r4/tests-fhir-r4/testNotEquivalent/testNotEquivalent17",
             "r4/tests-fhir-r4/testNotEquivalent/testNotEquivalent20",
             "r4/tests-fhir-r4/testNotEquivalent/testNotEquivalent21",
-            "r4/tests-fhir-r4/testNow/testNow1",
-            "r4/tests-fhir-r4/testNow/testNow2",
-            "r4/tests-fhir-r4/testNow/testNow3",
             "r4/tests-fhir-r4/testPower/testPower3",
             "r4/tests-fhir-r4/testPrecedence/testPrecedence3",
             "r4/tests-fhir-r4/testPrecedence/testPrecedence4",
@@ -281,9 +278,6 @@ public static Object[][] dataMethod() {
             "r4/tests-fhir-r4/testTypes/testStringIntegerLiteralIsNotQuantity",
             "r4/tests-fhir-r4/testTypes/testStringLiteralToString",
             "r4/tests-fhir-r4/testTypes/testStringQuantityWeekConvertsToQuantityFalse",
-            "r4/tests-fhir-r4/testUnion/testUnion4",
-            "r4/tests-fhir-r4/testUnion/testUnion5",
-            "r4/tests-fhir-r4/testUnion/testUnion8",
             "r4/tests-fhir-r4/testVariables/testVariables1",
             "r4/tests-fhir-r4/testVariables/testVariables2",
             "r4/tests-fhir-r4/testVariables/testVariables3",