diff --git a/src/dicognito/datetimeanonymizer.py b/src/dicognito/datetimeanonymizer.py
index 14ccade..90c6818 100644
--- a/src/dicognito/datetimeanonymizer.py
+++ b/src/dicognito/datetimeanonymizer.py
@@ -53,10 +53,7 @@ class DateTimeAnonymizer:
             dates = [data_element.value]
 
         times = []
-        if data_element.keyword.endswith("Date"):
-            time_name = data_element.keyword[:-4] + "Time"
-        elif data_element.keyword.startswith("Date"):
-            time_name = "Time" + data_element.keyword[4:]
+        time_name = data_element.keyword.replace("Date", "Time")
 
         if time_name in dataset:
             time_value = dataset.data_element(time_name).value
diff --git a/src/dicognito/release_notes.md b/src/dicognito/release_notes.md
index 61c64a5..d3285cd 100644
--- a/src/dicognito/release_notes.md
+++ b/src/dicognito/release_notes.md
@@ -1,8 +1,12 @@
-## 0.9.0
-
+### Fixed
+
+- Fails to anonymize object with Issue Date of Imaging Service Request ([#72](https://github.com/blairconrad/dicognito/issues/72))
+
+## 0.9.0
+
 ### New
 
-- Add option to write anonymized files to another directory([#69](https://github.com/blairconrad/dicognito/issues/69))
+- Add option to write anonymized files to another directory ([#69](https://github.com/blairconrad/dicognito/issues/69))
 
 ## 0.8.1
 

diff --git a/tests/test_anonymize_single_instance.py b/tests/test_anonymize_single_instance.py
index 567e996..23a05bc 100644
--- a/tests/test_anonymize_single_instance.py
+++ b/tests/test_anonymize_single_instance.py
@@ -452,6 +452,23 @@ def test_multivalued_date_and_time_pair_gets_anonymized():
     assert len(new_time) == len(original_time)
 
 
+def test_issue_date_of_imaging_service_request_gets_anonymized():
+    original_datetime = datetime.datetime(1974, 11, 3, 12, 15, 58)
+    original_date_string = original_datetime.strftime("%Y%m%d")
+    original_time_string = original_datetime.strftime("%H%M%S")
+
+    with load_test_instance() as dataset:
+        dataset.IssueDateOfImagingServiceRequest = original_date_string
+        dataset.IssueTimeOfImagingServiceRequest = original_time_string
+
+        anonymizer = Anonymizer()
+        anonymizer.anonymize(dataset)
+
+        new_date_string = dataset.IssueDateOfImagingServiceRequest
+        new_time_string = dataset.IssueTimeOfImagingServiceRequest
+    assert (new_date_string, new_time_string) != (original_date_string, original_time_string)
+
+
 @pytest.mark.parametrize(
     "datetime_name",
     [

Fails to anonymize object with Issue Date of Imaging Service Request
… because we look for "Date" at the beginning or end of the element name:

```
UnboundLocalError: With tag (200b, 102b) got exception: local variable 'time_name' referenced before assignment
Traceback (most recent call last):
  File "c:\program files\python37\lib\site-packages\pydicom\tag.py", line 30, in tag_in_exception
    yield
  File "c:\program files\python37\lib\site-packages\pydicom\dataset.py", line 1773, in walk
    callback(self, data_element)  # self = this Dataset
  File "c:\program files\python37\lib\site-packages\dicognito\anonymizer.py", line 120, in _anonymize_element
    if handler(dataset, data_element):
  File "c:\program files\python37\lib\site-packages\dicognito\datetimeanonymizer.py", line 43, in __call__
    self._anonymize_date_and_time(dataset, data_element)
  File "c:\program files\python37\lib\site-packages\dicognito\datetimeanonymizer.py", line 61, in _anonymize_date_and_time
    if time_name in dataset:
UnboundLocalError: local variable 'time_name' referenced before assignment
```
tests/test_anonymize_single_instance.py::test_issue_date_of_imaging_service_request_gets_anonymized
tests/test_anonymize_single_instance.py::test_minimal_instance_anonymizes_safely tests/test_anonymize_single_instance.py::test_nonidentifying_uis_are_left_alone[file_meta.MediaStorageSOPClassUID] tests/test_anonymize_single_instance.py::test_nonidentifying_uis_are_left_alone[file_meta.TransferSyntaxUID] tests/test_anonymize_single_instance.py::test_nonidentifying_uis_are_left_alone[file_meta.ImplementationClassUID] tests/test_anonymize_single_instance.py::test_nonidentifying_uis_are_left_alone[SOPClassUID] tests/test_anonymize_single_instance.py::test_nonidentifying_uis_are_left_alone[SourceImageSequence[0].ReferencedSOPClassUID] tests/test_anonymize_single_instance.py::test_identifying_uis_are_updated[file_meta.MediaStorageSOPInstanceUID] tests/test_anonymize_single_instance.py::test_identifying_uis_are_updated[SOPInstanceUID] tests/test_anonymize_single_instance.py::test_identifying_uis_are_updated[SourceImageSequence[0].ReferencedSOPInstanceUID] tests/test_anonymize_single_instance.py::test_identifying_uis_are_updated[StudyInstanceUID] tests/test_anonymize_single_instance.py::test_identifying_uis_are_updated[SeriesInstanceUID] tests/test_anonymize_single_instance.py::test_identifying_uis_are_updated[FrameOfReferenceUID] tests/test_anonymize_single_instance.py::test_repeated_identifying_uis_get_same_values[file_meta.MediaStorageSOPInstanceUID-SOPInstanceUID] tests/test_anonymize_single_instance.py::test_ids_are_anonymized[AccessionNumber] tests/test_anonymize_single_instance.py::test_ids_are_anonymized[FillerOrderNumberImagingServiceRequest] tests/test_anonymize_single_instance.py::test_ids_are_anonymized[FillerOrderNumberImagingServiceRequestRetired] tests/test_anonymize_single_instance.py::test_ids_are_anonymized[FillerOrderNumberProcedure] tests/test_anonymize_single_instance.py::test_ids_are_anonymized[IssuerOfPatientID] tests/test_anonymize_single_instance.py::test_ids_are_anonymized[OtherPatientIDs] tests/test_anonymize_single_instance.py::test_ids_are_anonymized[OtherPatientIDsSequence[0].PatientID] tests/test_anonymize_single_instance.py::test_ids_are_anonymized[OtherPatientIDsSequence[0].IssuerOfPatientID] tests/test_anonymize_single_instance.py::test_ids_are_anonymized[OtherPatientIDsSequence[1].PatientID] tests/test_anonymize_single_instance.py::test_ids_are_anonymized[OtherPatientIDsSequence[1].IssuerOfPatientID] tests/test_anonymize_single_instance.py::test_ids_are_anonymized[PatientID] tests/test_anonymize_single_instance.py::test_ids_are_anonymized[PerformedProcedureStepID] tests/test_anonymize_single_instance.py::test_ids_are_anonymized[PlacerOrderNumberImagingServiceRequest] tests/test_anonymize_single_instance.py::test_ids_are_anonymized[PlacerOrderNumberImagingServiceRequestRetired] tests/test_anonymize_single_instance.py::test_ids_are_anonymized[PlacerOrderNumberProcedure] tests/test_anonymize_single_instance.py::test_ids_are_anonymized[RequestAttributesSequence[0].RequestedProcedureID] tests/test_anonymize_single_instance.py::test_ids_are_anonymized[RequestAttributesSequence[0].ScheduledProcedureStepID] tests/test_anonymize_single_instance.py::test_ids_are_anonymized[ScheduledProcedureStepID] tests/test_anonymize_single_instance.py::test_ids_are_anonymized[StudyID] tests/test_anonymize_single_instance.py::test_other_patient_ids_anonymized_to_same_number_of_ids[2] tests/test_anonymize_single_instance.py::test_other_patient_ids_anonymized_to_same_number_of_ids[3] tests/test_anonymize_single_instance.py::test_issuer_of_patient_id_changed_if_not_empty tests/test_anonymize_single_instance.py::test_issuer_of_patient_id_not_added_if_empty tests/test_anonymize_single_instance.py::test_female_patient_name_gets_anonymized tests/test_anonymize_single_instance.py::test_male_patient_name_gets_anonymized tests/test_anonymize_single_instance.py::test_sex_other_patient_name_gets_anonymized tests/test_anonymize_single_instance.py::test_other_patient_names_anonymized_to_same_number_of_names[2] tests/test_anonymize_single_instance.py::test_other_patient_names_anonymized_to_same_number_of_names[3] tests/test_anonymize_single_instance.py::test_non_patient_names_get_anonymized[NameOfPhysiciansReadingStudy] tests/test_anonymize_single_instance.py::test_non_patient_names_get_anonymized[OperatorsName] tests/test_anonymize_single_instance.py::test_non_patient_names_get_anonymized[PatientBirthName] tests/test_anonymize_single_instance.py::test_non_patient_names_get_anonymized[PatientMotherBirthName] tests/test_anonymize_single_instance.py::test_non_patient_names_get_anonymized[PerformingPhysicianName] tests/test_anonymize_single_instance.py::test_non_patient_names_get_anonymized[ReferringPhysicianName] tests/test_anonymize_single_instance.py::test_non_patient_names_get_anonymized[RequestingPhysician] tests/test_anonymize_single_instance.py::test_non_patient_names_get_anonymized[ResponsiblePerson] tests/test_anonymize_single_instance.py::test_patient_address_gets_anonymized tests/test_anonymize_single_instance.py::test_extra_patient_attributes_are_removed[Occupation] tests/test_anonymize_single_instance.py::test_extra_patient_attributes_are_removed[PatientInsurancePlanCodeSequence] tests/test_anonymize_single_instance.py::test_extra_patient_attributes_are_removed[MilitaryRank] tests/test_anonymize_single_instance.py::test_extra_patient_attributes_are_removed[BranchOfService] tests/test_anonymize_single_instance.py::test_extra_patient_attributes_are_removed[PatientTelephoneNumbers] tests/test_anonymize_single_instance.py::test_extra_patient_attributes_are_removed[PatientTelecomInformation] tests/test_anonymize_single_instance.py::test_extra_patient_attributes_are_removed[PatientReligiousPreference] tests/test_anonymize_single_instance.py::test_extra_patient_attributes_are_removed[MedicalRecordLocator] tests/test_anonymize_single_instance.py::test_extra_patient_attributes_are_removed[ReferencedPatientPhotoSequence] tests/test_anonymize_single_instance.py::test_extra_patient_attributes_are_removed[ResponsibleOrganization] tests/test_anonymize_single_instance.py::test_equipment_gets_anonymized tests/test_anonymize_single_instance.py::test_requesting_service_gets_anonymized tests/test_anonymize_single_instance.py::test_current_patient_location_gets_anonymized tests/test_anonymize_single_instance.py::test_dates_and_times_get_anonymized_when_both_are_present[AcquisitionDate] tests/test_anonymize_single_instance.py::test_dates_and_times_get_anonymized_when_both_are_present[ContentDate] tests/test_anonymize_single_instance.py::test_dates_and_times_get_anonymized_when_both_are_present[InstanceCreationDate] tests/test_anonymize_single_instance.py::test_dates_and_times_get_anonymized_when_both_are_present[PatientBirthDate] tests/test_anonymize_single_instance.py::test_dates_and_times_get_anonymized_when_both_are_present[PerformedProcedureStepStartDate] tests/test_anonymize_single_instance.py::test_dates_and_times_get_anonymized_when_both_are_present[SeriesDate] tests/test_anonymize_single_instance.py::test_dates_and_times_get_anonymized_when_both_are_present[StudyDate] tests/test_anonymize_single_instance.py::test_date_gets_anonymized_when_there_is_no_time tests/test_anonymize_single_instance.py::test_date_gets_anonymized_when_date_has_various_lengths[20180202] tests/test_anonymize_single_instance.py::test_date_gets_anonymized_when_date_has_various_lengths[199901] tests/test_anonymize_single_instance.py::test_date_gets_anonymized_when_date_has_various_lengths[1983] tests/test_anonymize_single_instance.py::test_date_gets_anonymized_when_time_has_various_lengths[] tests/test_anonymize_single_instance.py::test_date_gets_anonymized_when_time_has_various_lengths[07] tests/test_anonymize_single_instance.py::test_date_gets_anonymized_when_time_has_various_lengths[0911] tests/test_anonymize_single_instance.py::test_date_gets_anonymized_when_time_has_various_lengths[131517] tests/test_anonymize_single_instance.py::test_date_gets_anonymized_when_time_has_various_lengths[192123.1] tests/test_anonymize_single_instance.py::test_date_gets_anonymized_when_time_has_various_lengths[192123.12] tests/test_anonymize_single_instance.py::test_date_gets_anonymized_when_time_has_various_lengths[192123.123] tests/test_anonymize_single_instance.py::test_date_gets_anonymized_when_time_has_various_lengths[192123.1234] tests/test_anonymize_single_instance.py::test_date_gets_anonymized_when_time_has_various_lengths[192123.12345] tests/test_anonymize_single_instance.py::test_date_gets_anonymized_when_time_has_various_lengths[192123.123456] tests/test_anonymize_single_instance.py::test_multivalued_date_with_no_time_pair_gets_anonymized tests/test_anonymize_single_instance.py::test_multivalued_date_and_time_pair_gets_anonymized tests/test_anonymize_single_instance.py::test_datetime_gets_anonymized[AcquisitionDateTime] tests/test_anonymize_single_instance.py::test_datetime_gets_anonymized[FrameReferenceDateTime] tests/test_anonymize_single_instance.py::test_datetime_gets_anonymized[FrameAcquisitionDateTime] tests/test_anonymize_single_instance.py::test_datetime_gets_anonymized[StartAcquisitionDateTime] tests/test_anonymize_single_instance.py::test_datetime_gets_anonymized[EndAcquisitionDateTime] tests/test_anonymize_single_instance.py::test_datetime_gets_anonymized[PerformedProcedureStepStartDateTime] tests/test_anonymize_single_instance.py::test_datetime_gets_anonymized[PerformedProcedureStepEndDateTime] tests/test_anonymize_single_instance.py::test_datetime_of_various_lengths_gets_anonymized[1947] tests/test_anonymize_single_instance.py::test_datetime_of_various_lengths_gets_anonymized[194711] tests/test_anonymize_single_instance.py::test_datetime_of_various_lengths_gets_anonymized[19471103] tests/test_anonymize_single_instance.py::test_datetime_of_various_lengths_gets_anonymized[1947110307] tests/test_anonymize_single_instance.py::test_datetime_of_various_lengths_gets_anonymized[194711030911] tests/test_anonymize_single_instance.py::test_datetime_of_various_lengths_gets_anonymized[19471103131517] tests/test_anonymize_single_instance.py::test_datetime_of_various_lengths_gets_anonymized[19471103192123.1] tests/test_anonymize_single_instance.py::test_datetime_of_various_lengths_gets_anonymized[19471103192123.12] tests/test_anonymize_single_instance.py::test_datetime_of_various_lengths_gets_anonymized[19471103192123.123] tests/test_anonymize_single_instance.py::test_datetime_of_various_lengths_gets_anonymized[19471103192123.1234] tests/test_anonymize_single_instance.py::test_datetime_of_various_lengths_gets_anonymized[19471103192123.12345] tests/test_anonymize_single_instance.py::test_datetime_of_various_lengths_gets_anonymized[19471103192123.123456] tests/test_anonymize_single_instance.py::test_multivalued_datetime_gets_anonymized tests/test_anonymize_single_instance.py::test_no_sex_still_changes_patient_name tests/test_anonymize_single_instance.py::test_deidentification_method_set_properly[None-DICOGNITO] tests/test_anonymize_single_instance.py::test_deidentification_method_set_properly[DICOGNITO-DICOGNITO] tests/test_anonymize_single_instance.py::test_deidentification_method_set_properly[SOMETHINGELSE-expected2] tests/test_anonymize_single_instance.py::test_deidentification_method_set_properly[SOMETHING\\SOMETHINGELSE-expected3] tests/test_anonymize_single_instance.py::test_deidentification_method_set_properly[DICOGNITO\\SOMETHINGELSE-expected4] tests/test_anonymize_single_instance.py::test_patient_identity_removed[None-None-None] tests/test_anonymize_single_instance.py::test_patient_identity_removed[None-YES-None] tests/test_anonymize_single_instance.py::test_patient_identity_removed[None-NO-YES] tests/test_anonymize_single_instance.py::test_patient_identity_removed[NO-None-NO] tests/test_anonymize_single_instance.py::test_patient_identity_removed[NO-YES-NO] tests/test_anonymize_single_instance.py::test_patient_identity_removed[NO-NO-YES] tests/test_anonymize_single_instance.py::test_patient_identity_removed[YES-None-YES] tests/test_anonymize_single_instance.py::test_patient_identity_removed[YES-YES-YES] tests/test_anonymize_single_instance.py::test_patient_identity_removed[YES-NO-YES]