diff --git a/iati-activities-schema.xsd b/iati-activities-schema.xsd
index 7e0d71ce..4096473c 100644
--- a/iati-activities-schema.xsd
+++ b/iati-activities-schema.xsd
@@ -468,7 +468,7 @@
     </xsd:complexType>
   </xsd:element>
 
-  <xsd:element name="default-aid-type">
+  <xsd:element name="default-aid-type" type="aidTypeBase">
     <xsd:annotation>
       <xsd:documentation xml:lang="en">
         The type of aid being supplied (project-type intervention,
@@ -477,19 +477,6 @@
         be overridden at the individual transaction level.
       </xsd:documentation>
     </xsd:annotation>
-    <xsd:complexType>
-      <xsd:sequence>
-        <xsd:any namespace="##other" processContents="lax" minOccurs="0" maxOccurs="unbounded"/>
-      </xsd:sequence>
-      <xsd:attribute name="code" type="xsd:string"  use="required">
-        <xsd:annotation>
-          <xsd:documentation xml:lang="en">
-            A code from the specified vocabulary.
-          </xsd:documentation>
-        </xsd:annotation>
-      </xsd:attribute>
-      <xsd:anyAttribute processContents="lax" namespace="##other"/>
-    </xsd:complexType>
   </xsd:element>
 
   <xsd:element name="default-finance-type">
@@ -1309,7 +1296,7 @@
             <xsd:anyAttribute processContents="lax" namespace="##other"/>
           </xsd:complexType>
         </xsd:element>
-        <xsd:element name="aid-type" minOccurs="0" maxOccurs="unbounded">
+        <xsd:element name="aid-type" type="aidTypeBase" minOccurs="0" maxOccurs="unbounded">
           <xsd:annotation>
             <xsd:documentation xml:lang="en">
               Optional element to override the top-level
@@ -1317,19 +1304,6 @@
               transaction-by-transaction basis if needed.
             </xsd:documentation>
           </xsd:annotation>
-          <xsd:complexType>
-            <xsd:sequence>
-              <xsd:any namespace="##other" processContents="lax" minOccurs="0" maxOccurs="unbounded"/>
-            </xsd:sequence>
-            <xsd:attribute name="code" type="xsd:string"  use="required">
-              <xsd:annotation>
-                <xsd:documentation xml:lang="en">
-                  A code from the OECD DAC CRS "Type of aid" codelist
-                </xsd:documentation>
-              </xsd:annotation>
-            </xsd:attribute>
-            <xsd:anyAttribute processContents="lax" namespace="##other"/>
-          </xsd:complexType>
         </xsd:element>
         <xsd:element name="tied-status" minOccurs="0" maxOccurs="1">
           <xsd:annotation>
@@ -2683,6 +2657,27 @@
       <xsd:anyAttribute processContents="lax" namespace="##other"/>
     </xsd:complexType>
   </xsd:element>
+  
+    <xsd:complexType name="aidTypeBase">
+    <xsd:sequence>
+      <xsd:any namespace="##other" processContents="lax" minOccurs="0" maxOccurs="unbounded"/>
+    </xsd:sequence>
+    <xsd:attribute name="code" type="xsd:string"  use="required">
+      <xsd:annotation>
+        <xsd:documentation xml:lang="en">
+          A code from the specified vocabulary.
+        </xsd:documentation>
+      </xsd:annotation>
+    </xsd:attribute>
+    <xsd:attribute name="vocabulary" type="xsd:string">
+      <xsd:annotation>
+        <xsd:documentation xml:lang="en">
+          A code for the vocabulary aid-type classifications. If omitted the AidType (OECD DAC) codelist is assumed. The code must be a valid value in the AidTypeVocabulary codelist.
+        </xsd:documentation>
+      </xsd:annotation>
+    </xsd:attribute>
+    <xsd:anyAttribute processContents="lax" namespace="##other"/>
+  </xsd:complexType>
 
   <xsd:complexType name="currencyType">
     <xsd:annotation>
diff --git a/tests/should-pass/iati-activities/iati-activity/default-aid-type/_vocabulary/attribute-exists.xml b/tests/should-pass/iati-activities/iati-activity/default-aid-type/_vocabulary/attribute-exists.xml
new file mode 100644
index 00000000..80b94f9b
--- /dev/null
+++ b/tests/should-pass/iati-activities/iati-activity/default-aid-type/_vocabulary/attribute-exists.xml
@@ -0,0 +1,21 @@
+<?xml version="1.0"?>
+
+<iati-activities version="xx">
+  <iati-activity>
+    <iati-identifier></iati-identifier>
+    <reporting-org type="xx" ref="xx"><narrative>Organisation name</narrative></reporting-org>
+    <title>
+      <narrative>Xxxxxxx</narrative>
+    </title>
+    <description>
+      <narrative>Xxxxxxx</narrative>
+    </description>
+    <participating-org role="xx"></participating-org>
+    <activity-status code="xx"/>
+    <activity-date type="xx" iso-date="2013-11-27"/>
+    <activity-date type="xx" iso-date="2013-11-27">
+      <narrative>Some stuff ere</narrative>
+    </activity-date>
+    <default-aid-type code="xx" vocabulary="xx"/><!-- PASS: Optional attribute present -->
+  </iati-activity>
+</iati-activities>
diff --git a/tests/should-pass/iati-activities/iati-activity/default-aid-type/element-exists-with-required-subelements-only.xml b/tests/should-pass/iati-activities/iati-activity/default-aid-type/element-exists-with-required-subelements-only.xml
new file mode 100644
index 00000000..b7779f3f
--- /dev/null
+++ b/tests/should-pass/iati-activities/iati-activity/default-aid-type/element-exists-with-required-subelements-only.xml
@@ -0,0 +1,21 @@
+<?xml version="1.0"?>
+
+<iati-activities version="xx">
+  <iati-activity>
+    <iati-identifier></iati-identifier>
+    <reporting-org type="xx" ref="xx"><narrative>Organisation name</narrative></reporting-org>
+    <title>
+      <narrative>Xxxxxxx</narrative>
+    </title>
+    <description>
+      <narrative>Xxxxxxx</narrative>
+    </description>
+    <participating-org role="xx"></participating-org>
+    <activity-status code="xx"/>
+    <activity-date type="xx" iso-date="2013-11-27"/>
+    <activity-date type="xx" iso-date="2013-11-27">
+      <narrative>Some stuff ere</narrative>
+    </activity-date>
+    <default-aid-type code="xx"/><!-- PASS: Optional element present with only required attributes -->
+  </iati-activity>
+</iati-activities>
diff --git a/tests/should-pass/iati-activities/iati-activity/transaction/aid-type/_vocabulary/attribute-exists.xml b/tests/should-pass/iati-activities/iati-activity/transaction/aid-type/_vocabulary/attribute-exists.xml
new file mode 100644
index 00000000..a2a10e6c
--- /dev/null
+++ b/tests/should-pass/iati-activities/iati-activity/transaction/aid-type/_vocabulary/attribute-exists.xml
@@ -0,0 +1,23 @@
+<?xml version="1.0"?>
+
+<iati-activities version="xx">
+  <iati-activity>
+    <iati-identifier></iati-identifier>
+    <reporting-org type="xx" ref="xx"><narrative>Organisation name</narrative></reporting-org>
+    <title>
+      <narrative>Xxxxxxx</narrative>
+    </title>
+    <description>
+      <narrative>Xxxxxxx</narrative>
+    </description>
+    <participating-org role="xx"></participating-org>
+    <activity-status code="xx"/>
+    <activity-date type="xx" iso-date="2013-11-27"/>
+    <transaction>
+      <transaction-type code="xx"/>
+      <transaction-date iso-date="2010-07-07"/>
+      <value value-date="2010-07-07">100</value>
+      <aid-type code="xx" vocabulary="xx"/><!--PASS: Optional attribute present -->
+    </transaction>
+  </iati-activity>
+</iati-activities>
diff --git a/tests/should-pass/iati-activities/iati-activity/transaction/aid-type/element-present-once.xml b/tests/should-pass/iati-activities/iati-activity/transaction/aid-type/element-present-once.xml
index f788f4f6..8458979a 100644
--- a/tests/should-pass/iati-activities/iati-activity/transaction/aid-type/element-present-once.xml
+++ b/tests/should-pass/iati-activities/iati-activity/transaction/aid-type/element-present-once.xml
@@ -17,7 +17,7 @@
       <transaction-type code="xx"/>
       <transaction-date iso-date="2010-07-07"/>
       <value value-date="2010-07-07">100</value>
-      <aid-type code="xx"/><!--PASS: Optional element present once -->
+      <aid-type code="xx"/><!--PASS: Optional element present once with only required attributes -->
     </transaction>
   </iati-activity>
 </iati-activities>