diff --git a/src/main/java/com/gocardless/errors/ApiErrorResponse.java b/src/main/java/com/gocardless/errors/ApiErrorResponse.java
index 006b791f..dbfac8cb 100644
--- a/src/main/java/com/gocardless/errors/ApiErrorResponse.java
+++ b/src/main/java/com/gocardless/errors/ApiErrorResponse.java
@@ -23,6 +23,10 @@ private ApiErrorResponse(String message, ErrorType type, String documentationUrl
         this.errors = errors;
     }
 
+    public static ApiErrorResponse fromMessage(String message, int code) {
+        return new ApiErrorResponse(message, ErrorType.GOCARDLESS, null, null, code, null);
+    }
+
     String getMessage() {
         return message;
     }
diff --git a/src/main/java/com/gocardless/http/HttpClient.java b/src/main/java/com/gocardless/http/HttpClient.java
index 80163912..7f26128e 100644
--- a/src/main/java/com/gocardless/http/HttpClient.java
+++ b/src/main/java/com/gocardless/http/HttpClient.java
@@ -177,7 +177,7 @@ private <T> T parseResponseBody(ApiRequest<T> request, Response response) {
     private GoCardlessException handleErrorResponse(Response response) {
         try {
             String responseBody = response.body().string();
-            return responseParser.parseError(responseBody);
+            return responseParser.parseError(responseBody, response.code());
         } catch (IOException e) {
             throw new GoCardlessNetworkException("Failed to read response body", e);
         }
diff --git a/src/main/java/com/gocardless/http/ResponseParser.java b/src/main/java/com/gocardless/http/ResponseParser.java
index 504a56ec..494af8f3 100644
--- a/src/main/java/com/gocardless/http/ResponseParser.java
+++ b/src/main/java/com/gocardless/http/ResponseParser.java
@@ -51,8 +51,20 @@ <T> ListResponse<T> parsePage(String responseBody, String envelope, TypeToken<Li
         return new ListResponse<>(ImmutableList.copyOf(items), meta, linked);
     }
 
-    GoCardlessApiException parseError(String responseBody) {
-        ApiErrorResponse error = parseSingle(responseBody, "error", ApiErrorResponse.class);
+    GoCardlessApiException parseError(String responseBody, int statusCode) {
+        JsonElement json;
+        try {
+            json = new JsonParser().parse(responseBody);
+        } catch (JsonSyntaxException e) {
+            throw new MalformedResponseException(responseBody);
+        }
+        JsonElement errorElement = json.getAsJsonObject().get("error");
+        if (errorElement.isJsonPrimitive()) {
+            ApiErrorResponse error =
+                    ApiErrorResponse.fromMessage(errorElement.getAsString(), statusCode);
+            return GoCardlessErrorMapper.toException(error);
+        }
+        ApiErrorResponse error = gson.fromJson(errorElement, ApiErrorResponse.class);
         return GoCardlessErrorMapper.toException(error);
     }
 }
diff --git a/src/main/java/com/gocardless/resources/ScenarioSimulator.java b/src/main/java/com/gocardless/resources/ScenarioSimulator.java
index 81f200e0..23176c2f 100644
--- a/src/main/java/com/gocardless/resources/ScenarioSimulator.java
+++ b/src/main/java/com/gocardless/resources/ScenarioSimulator.java
@@ -81,9 +81,8 @@ private ScenarioSimulator() {
      * `pending_submission` state. Not compatible with Autogiro, BECS NZ, and PAD mandates, which do
      * not expire.</li>
      * <li>`mandate_transferred`: Transitions a mandate through to `transferred`, having been
-     * submitted to the banks, set up successfully and then moved to a new bank account due to the
-     * customer using the UK's Current Account Switching Service (CASS). It must start in the
-     * `pending_submission` state. Only compatible with Bacs mandates.</li>
+     * submitted to the banks, set up successfully and then moved to a new bank account due. It must
+     * start in the `pending_submission` state. Only compatible with Bacs and SEPA mandates.</li>
      * <li>`mandate_transferred_with_resubmission`: Transitions a mandate through `transferred` and
      * resubmits it to the banks, can be caused be the UK's Current Account Switching Service (CASS)
      * or when a customer contacts GoCardless to change their bank details. It must start in the
diff --git a/src/main/java/com/gocardless/services/BillingRequestTemplateService.java b/src/main/java/com/gocardless/services/BillingRequestTemplateService.java
index 53261738..5125d10c 100644
--- a/src/main/java/com/gocardless/services/BillingRequestTemplateService.java
+++ b/src/main/java/com/gocardless/services/BillingRequestTemplateService.java
@@ -57,7 +57,7 @@ public BillingRequestTemplateGetRequest get(String identity) {
     }
 
     /**
-      * 
+      *  
      */
     public BillingRequestTemplateCreateRequest create() {
         return new BillingRequestTemplateCreateRequest(httpClient);
diff --git a/src/main/java/com/gocardless/services/CustomerService.java b/src/main/java/com/gocardless/services/CustomerService.java
index fb500697..28c2c3fa 100644
--- a/src/main/java/com/gocardless/services/CustomerService.java
+++ b/src/main/java/com/gocardless/services/CustomerService.java
@@ -302,11 +302,20 @@ protected boolean hasBody() {
      * Returns a [cursor-paginated](#api-usage-cursor-pagination) list of your customers.
      */
     public static final class CustomerListRequest<S> extends ListRequest<S, Customer> {
+        private ActionRequired actionRequired;
         private CreatedAt createdAt;
         private Currency currency;
         private SortDirection sortDirection;
         private SortField sortField;
 
+        /**
+         * Boolean indicating whether the customer has any actions required.
+         */
+        public CustomerListRequest<S> withActionRequired(ActionRequired actionRequired) {
+            this.actionRequired = actionRequired;
+            return this;
+        }
+
         /**
          * Cursor pointing to the start of the desired set.
          */
@@ -428,6 +437,9 @@ public CustomerListRequest<S> withHeader(String headerName, String headerValue)
         protected Map<String, Object> getQueryParams() {
             ImmutableMap.Builder<String, Object> params = ImmutableMap.builder();
             params.putAll(super.getQueryParams());
+            if (actionRequired != null) {
+                params.put("action_required", actionRequired);
+            }
             if (createdAt != null) {
                 params.putAll(createdAt.getQueryParams());
             }
@@ -458,6 +470,18 @@ protected TypeToken<List<Customer>> getTypeToken() {
             return new TypeToken<List<Customer>>() {};
         }
 
+        public enum ActionRequired {
+            @SerializedName("true")
+            TRUE, @SerializedName("false")
+            FALSE, @SerializedName("unknown")
+            UNKNOWN;
+
+            @Override
+            public String toString() {
+                return name().toLowerCase();
+            }
+        }
+
         public enum Currency {
             @SerializedName("AUD")
             AUD, @SerializedName("CAD")
diff --git a/src/main/java/com/gocardless/services/MandateImportEntryService.java b/src/main/java/com/gocardless/services/MandateImportEntryService.java
index cf79aa06..b5fed44f 100644
--- a/src/main/java/com/gocardless/services/MandateImportEntryService.java
+++ b/src/main/java/com/gocardless/services/MandateImportEntryService.java
@@ -473,6 +473,25 @@ public MandateImportEntryCreateRequest withMandate(Mandate mandate) {
             return this;
         }
 
+        /**
+         * This field is ACH specific, sometimes referred to as [SEC
+         * code](https://www.moderntreasury.com/learn/sec-codes).
+         * 
+         * This is the way that the payer gives authorisation to the merchant. web: Authorisation is
+         * Internet Initiated or via Mobile Entry (maps to SEC code: WEB) telephone: Authorisation
+         * is provided orally over telephone (maps to SEC code: TEL) paper: Authorisation is
+         * provided in writing and signed, or similarly authenticated (maps to SEC code: PPD)
+         * 
+         */
+        public MandateImportEntryCreateRequest withMandateAuthorisationSource(
+                Mandate.AuthorisationSource authorisationSource) {
+            if (mandate == null) {
+                mandate = new Mandate();
+            }
+            mandate.withAuthorisationSource(authorisationSource);
+            return this;
+        }
+
         /**
          * Key-value store of custom data. Up to 3 keys are permitted, with key names up to 50
          * characters and values up to 500 characters.
@@ -856,9 +875,26 @@ public Links withMandateImport(String mandateImport) {
         }
 
         public static class Mandate {
+            private AuthorisationSource authorisationSource;
             private Map<String, String> metadata;
             private String reference;
 
+            /**
+             * This field is ACH specific, sometimes referred to as [SEC
+             * code](https://www.moderntreasury.com/learn/sec-codes).
+             * 
+             * This is the way that the payer gives authorisation to the merchant. web:
+             * Authorisation is Internet Initiated or via Mobile Entry (maps to SEC code: WEB)
+             * telephone: Authorisation is provided orally over telephone (maps to SEC code: TEL)
+             * paper: Authorisation is provided in writing and signed, or similarly authenticated
+             * (maps to SEC code: PPD)
+             * 
+             */
+            public Mandate withAuthorisationSource(AuthorisationSource authorisationSource) {
+                this.authorisationSource = authorisationSource;
+                return this;
+            }
+
             /**
              * Key-value store of custom data. Up to 3 keys are permitted, with key names up to 50
              * characters and values up to 500 characters.
@@ -877,6 +913,19 @@ public Mandate withReference(String reference) {
                 this.reference = reference;
                 return this;
             }
+
+            public enum AuthorisationSource {
+                @SerializedName("web")
+                WEB, @SerializedName("telephone")
+                TELEPHONE, @SerializedName("paper")
+                PAPER, @SerializedName("unknown")
+                UNKNOWN;
+
+                @Override
+                public String toString() {
+                    return name().toLowerCase();
+                }
+            }
         }
     }
 
diff --git a/src/main/java/com/gocardless/services/OutboundPaymentService.java b/src/main/java/com/gocardless/services/OutboundPaymentService.java
index f62957cb..a756f2d9 100644
--- a/src/main/java/com/gocardless/services/OutboundPaymentService.java
+++ b/src/main/java/com/gocardless/services/OutboundPaymentService.java
@@ -37,7 +37,7 @@ public OutboundPaymentService(HttpClient httpClient) {
     }
 
     /**
-      * 
+      *  
      */
     public OutboundPaymentCreateRequest create() {
         return new OutboundPaymentCreateRequest(httpClient);
diff --git a/src/test/java/com/gocardless/http/ResponseParserTest.java b/src/test/java/com/gocardless/http/ResponseParserTest.java
index 2254768c..f2bd1dee 100644
--- a/src/test/java/com/gocardless/http/ResponseParserTest.java
+++ b/src/test/java/com/gocardless/http/ResponseParserTest.java
@@ -69,7 +69,7 @@ public void shouldParsePage() throws IOException {
     public void shouldParseInvalidApiUsageError() throws IOException {
         URL resource = Resources.getResource("fixtures/invalid_api_usage.json");
         String responseBody = Resources.toString(resource, UTF_8);
-        GoCardlessApiException exception = parser.parseError(responseBody);
+        GoCardlessApiException exception = parser.parseError(responseBody, 400);
         assertThat(exception).isInstanceOf(InvalidApiUsageException.class);
         assertThat(exception.getType()).isEqualTo(INVALID_API_USAGE);
         assertThat(exception.getMessage()).isEqualTo("Invalid document structure");
@@ -88,7 +88,7 @@ public void shouldParseInvalidApiUsageError() throws IOException {
     public void shouldParseInvalidStateError() throws IOException {
         URL resource = Resources.getResource("fixtures/invalid_state.json");
         String responseBody = Resources.toString(resource, UTF_8);
-        GoCardlessApiException exception = parser.parseError(responseBody);
+        GoCardlessApiException exception = parser.parseError(responseBody, 409);
         assertThat(exception).isInstanceOf(InvalidStateException.class);
         assertThat(exception.getType()).isEqualTo(INVALID_STATE);
         assertThat(exception.getMessage()).isEqualTo("Bank account already exists");
@@ -108,7 +108,7 @@ public void shouldParseInvalidStateError() throws IOException {
     public void shouldParseValidationFailedError() throws IOException {
         URL resource = Resources.getResource("fixtures/validation_failed.json");
         String responseBody = Resources.toString(resource, UTF_8);
-        GoCardlessApiException exception = parser.parseError(responseBody);
+        GoCardlessApiException exception = parser.parseError(responseBody, 422);
         assertThat(exception).isInstanceOf(ValidationFailedException.class);
         assertThat(exception.getType()).isEqualTo(VALIDATION_FAILED);
         assertThat(exception.getMessage()).isEqualTo(
@@ -133,7 +133,7 @@ public void shouldParseValidationFailedError() throws IOException {
     public void shouldParseInternalError() throws IOException {
         URL resource = Resources.getResource("fixtures/internal_error.json");
         String responseBody = Resources.toString(resource, UTF_8);
-        GoCardlessApiException exception = parser.parseError(responseBody);
+        GoCardlessApiException exception = parser.parseError(responseBody, 500);
         assertThat(exception).isInstanceOf(GoCardlessInternalException.class);
         assertThat(exception.getType()).isEqualTo(GOCARDLESS);
         assertThat(exception.getMessage()).isEqualTo("THE BEES THEY'RE IN MY EYES");
@@ -145,19 +145,32 @@ public void shouldParseInternalError() throws IOException {
         assertThat(exception.getErrors()).isEmpty();
     }
 
+    @Test
+    public void shouldParseStringError() throws IOException {
+        URL resource = Resources.getResource("fixtures/string_error.json");
+        String responseBody = Resources.toString(resource, UTF_8);
+        GoCardlessApiException exception = parser.parseError(responseBody, 400);
+        assertThat(exception).isInstanceOf(GoCardlessInternalException.class);
+        assertThat(exception.getType()).isEqualTo(GOCARDLESS);
+        assertThat(exception.getMessage()).isEqualTo("bank_authorisation_expired");
+        assertThat(exception.getErrorMessage()).isEqualTo("bank_authorisation_expired");
+        assertThat(exception.getCode()).isEqualTo(400);
+        assertThat(exception.getErrors()).isEmpty();
+    }
+
     @Test
     public void shouldHandleNonJsonResponse() throws IOException {
         exception.expect(MalformedResponseException.class);
         URL resource = Resources.getResource("fixtures/non_json_response.html");
         String responseBody = Resources.toString(resource, UTF_8);
-        parser.parseError(responseBody);
+        parser.parseError(responseBody, 500);
     }
 
     @Test
     public void shouldHandleAuthenticationError() throws IOException {
         URL resource = Resources.getResource("fixtures/unauthorized_error.json");
         String responseBody = Resources.toString(resource, UTF_8);
-        GoCardlessApiException exception = parser.parseError(responseBody);
+        GoCardlessApiException exception = parser.parseError(responseBody, 401);
         assertThat(exception).isInstanceOf(AuthenticationException.class);
         assertThat(exception.getMessage()).isEqualTo("Unauthorized");
         assertThat(exception.getDocumentationUrl())
@@ -174,7 +187,7 @@ public void shouldHandleAuthenticationError() throws IOException {
     public void shouldHandleRateLimitError() throws IOException {
         URL resource = Resources.getResource("fixtures/rate_limit_exceeded.json");
         String responseBody = Resources.toString(resource, UTF_8);
-        GoCardlessApiException exception = parser.parseError(responseBody);
+        GoCardlessApiException exception = parser.parseError(responseBody, 429);
         assertThat(exception).isInstanceOf(RateLimitException.class);
         assertThat(exception.getMessage()).isEqualTo("Rate limit exceeded");
         assertThat(exception.getDocumentationUrl())
@@ -191,7 +204,7 @@ public void shouldHandleRateLimitError() throws IOException {
     public void shouldHandlePermissionException() throws IOException {
         URL resource = Resources.getResource("fixtures/insufficient_permission.json");
         String responseBody = Resources.toString(resource, UTF_8);
-        GoCardlessApiException exception = parser.parseError(responseBody);
+        GoCardlessApiException exception = parser.parseError(responseBody, 403);
         assertThat(exception).isInstanceOf(PermissionException.class);
         assertThat(exception.getMessage()).isEqualTo("Insufficient permissions");
         assertThat(exception.getDocumentationUrl()).isEqualTo(
diff --git a/src/test/resources/fixtures/string_error.json b/src/test/resources/fixtures/string_error.json
new file mode 100644
index 00000000..70870dd1
--- /dev/null
+++ b/src/test/resources/fixtures/string_error.json
@@ -0,0 +1 @@
+{"error": "bank_authorisation_expired"}
\ No newline at end of file