diff --git a/ActivityDefinition/DGTS-ActivityDefinition-Example.json b/ActivityDefinition/DGTS-ActivityDefinition-Example.json
index e99be91..a24248d 100644
--- a/ActivityDefinition/DGTS-ActivityDefinition-Example.json
+++ b/ActivityDefinition/DGTS-ActivityDefinition-Example.json
@@ -4,8 +4,13 @@
   "url": "http://fhir.nhs.uk/ActivityDefinition/GT1",
   "identifier": [
     {
-      "system": "http://fhir.nhs.uk/Id/Genomics-DGTS",
+      "system": "https://fhir.nhs.uk/Id/England-DigitalGenomicTestServices",
       "value": "GT1"
+    },
+    {
+      "system": "https://fhir.nhs.uk/Id/England-GenomicTestDirectory",
+      "value": "R47.2",
+      "use": "old"
     }
   ],
   "title": "15q11 critical region (AS/PWS) - MLPA or equivalent",
diff --git a/Library/DGTS-Library-Example.json b/Library/DGTS-Library-Example.json
index 8a268b3..4a92502 100644
--- a/Library/DGTS-Library-Example.json
+++ b/Library/DGTS-Library-Example.json
@@ -21,19 +21,19 @@
     {
       "name": "target_disease_required",
       "use": "in",
-      "max": "0",
+      "min": 0,
       "type": "Coding"
     },
     {
       "name": "target_gene_required",
       "use": "in",
-      "max": "0",
+      "min": 0,
       "type": "Coding"
     },
     {
       "name": "target_variant_required",
       "use": "in",
-      "max": "0",
+      "min": 0,
       "type": "Coding"
     }
   ]
diff --git a/NamingSystem/NamingSystem-England-DigitalGenomicTestServices-Identifier.json b/NamingSystem/NamingSystem-England-DigitalGenomicTestServices-Identifier.json
new file mode 100644
index 0000000..84a85d2
--- /dev/null
+++ b/NamingSystem/NamingSystem-England-DigitalGenomicTestServices-Identifier.json
@@ -0,0 +1,43 @@
+{
+  "resourceType": "NamingSystem",
+  "id": "England-DigitalGenomicTestServices-Identifier",
+  "name": "EnglandDigitalGenomicTestServicesIdentifier",
+  "status": "draft",
+  "kind": "identifier",
+  "date": "2025-12-11",
+  "publisher": "NHS England",
+  "contact": [
+    {
+      "name": "NHS England",
+      "telecom": [
+        {
+          "system": "email",
+          "value": "interoperabilityteam@nhs.net",
+          "use": "work",
+          "rank": 1
+        }
+      ]
+    },
+    {
+      "name": "NHS Genomic Medicine Service",
+      "telecom": [
+        {
+          "system": "email",
+          "value": "england.genomics@nhs.net",
+          "use": "work",
+          "rank": 1
+        }
+      ]
+    }
+  ],
+  "responsible": "NHS Genomic Interop Programme",
+  "description": "NamingSystem for Digital Genomic Test Services",
+	"usage": "Used to define the system for Genomic Test Services codes within ActivityDefinition and PlanDefinition resources",
+  "uniqueId":  [
+    {
+      "type": "uri",
+      "value": "https://fhir.nhs.uk/Id/England-DigitalGenomicTestServices",
+      "preferred": true
+    }
+  ]
+}
\ No newline at end of file
diff --git a/NamingSystem/NamingSystem-England-GenomicTestDirectory-Identifier.json b/NamingSystem/NamingSystem-England-GenomicTestDirectory-Identifier.json
new file mode 100644
index 0000000..887419e
--- /dev/null
+++ b/NamingSystem/NamingSystem-England-GenomicTestDirectory-Identifier.json
@@ -0,0 +1,43 @@
+{
+  "resourceType": "NamingSystem",
+  "id": "England-GenomicTestDirectory-Identifier",
+  "name": "EnglandGenomicTestDirectoryIdentifier",
+  "status": "draft",
+  "kind": "identifier",
+  "date": "2025-12-11",
+  "publisher": "NHS England",
+  "contact": [
+    {
+      "name": "NHS England",
+      "telecom": [
+        {
+          "system": "email",
+          "value": "interoperabilityteam@nhs.net",
+          "use": "work",
+          "rank": 1
+        }
+      ]
+    },
+    {
+      "name": "NHS Genomic Medicine Service",
+      "telecom": [
+        {
+          "system": "email",
+          "value": "england.genomics@nhs.net",
+          "use": "work",
+          "rank": 1
+        }
+      ]
+    }
+  ],
+  "responsible": "NHS Genomic Interop Programme",
+  "description": "NamingSystem for Genomic Test Directory Identifier System",
+	"usage": "Used to define the system for Genomic Test Directory codes within ActivityDefinition and PlanDefinition resources",
+  "uniqueId":  [
+    {
+      "type": "uri",
+      "value": "https://fhir.nhs.uk/Id/England-GenomicTestDirectory",
+      "preferred": true
+    }
+  ]
+}
\ No newline at end of file
diff --git a/PlanDefinition/DGTS-PlanDefinition-Example.json b/PlanDefinition/DGTS-PlanDefinition-Example.json
index a2d0189..a207cd8 100644
--- a/PlanDefinition/DGTS-PlanDefinition-Example.json
+++ b/PlanDefinition/DGTS-PlanDefinition-Example.json
@@ -4,8 +4,13 @@
   "url": "http://fhir.nhs.uk/PlanDefinition/TP231",
   "identifier": [
     {
-      "system": "http://fhir.nhs.uk/Id/Genomics-DGTS-TestPackage",
+      "system": "https://fhir.nhs.uk/Id/England-DigitalGenomicTestServices",
       "value": "TP231"
+    },
+    {
+      "system": "https://fhir.nhs.uk/Id/England-GenomicTestDirectory",
+      "value": "R47",
+      "use": "old"
     }
   ],
   "title": "Angelman syndrome",