diff --git a/lib/codegen/fromcto/plantuml/plantumlvisitor.js b/lib/codegen/fromcto/plantuml/plantumlvisitor.js
index d3b9614b..dbcb207c 100644
--- a/lib/codegen/fromcto/plantuml/plantumlvisitor.js
+++ b/lib/codegen/fromcto/plantuml/plantumlvisitor.js
@@ -57,6 +57,22 @@ class PlantUMLVisitor extends DiagramVisitor {
         this.writeDeclaration(classDeclaration, parameters, '(A,green)' );
     }
 
+    /**
+     * Visitor design pattern
+     * @param {MapDeclaration} mapDeclaration - the object being visited
+     * @param {Object} parameters  - the parameter
+     * @protected
+     */
+    visitMapDeclaration(mapDeclaration, parameters) {
+        const fqn       = this.escapeString(mapDeclaration.getFullyQualifiedName());
+        const keyType   = mapDeclaration.getKey().getType();
+        const valueType = mapDeclaration.getValue().getType();
+
+        parameters.fileWriter.writeLine(0, `map "${fqn}: Map<${keyType}, ${valueType}>" as ${fqn} {`);
+        parameters.fileWriter.writeLine(0, '}' );
+    }
+
+
     /**
      * Visitor design pattern
      * @param {ClassDeclaration} classDeclaration - the object being visited
diff --git a/test/codegen/__snapshots__/codegen.js.snap b/test/codegen/__snapshots__/codegen.js.snap
index dd92e2f9..3425c333 100644
--- a/test/codegen/__snapshots__/codegen.js.snap
+++ b/test/codegen/__snapshots__/codegen.js.snap
@@ -3799,6 +3799,8 @@ class org.acme.hr.base.TShirtSizeType << (E,grey) >> {
    + LARGE
 }
 org.acme.hr.base.TShirtSizeType --|> concerto_1_0_0.Concept
+map "org.acme.hr.base.EmployeeTShirtSizes: Map<SSN, TShirtSizeType>" as org.acme.hr.base.EmployeeTShirtSizes {
+}
 class org.acme.hr.base.Address {
    + String street
    + String city
@@ -3807,6 +3809,18 @@ class org.acme.hr.base.Address {
    + String country
 }
 org.acme.hr.base.Address --|> concerto_1_0_0.Concept
+map "org.acme.hr.CompanyProperties: Map<String, String>" as org.acme.hr.CompanyProperties {
+}
+map "org.acme.hr.EmployeeLoginTimes: Map<String, Time>" as org.acme.hr.EmployeeLoginTimes {
+}
+map "org.acme.hr.EmployeeSocialSecurityNumbers: Map<String, SSN>" as org.acme.hr.EmployeeSocialSecurityNumbers {
+}
+map "org.acme.hr.NextOfKin: Map<KinName, KinTelephone>" as org.acme.hr.NextOfKin {
+}
+map "org.acme.hr.EmployeeProfiles: Map<String, Concept>" as org.acme.hr.EmployeeProfiles {
+}
+map "org.acme.hr.EmployeeDirectory: Map<SSN, Employee>" as org.acme.hr.EmployeeDirectory {
+}
 class org.acme.hr.Company {
    + String name
    + Address headquarters
@@ -5800,6 +5814,8 @@ class org.acme.hr.base_1_0_0.TShirtSizeType << (E,grey) >> {
    + MEDIUM
    + LARGE
 }
+map "org.acme.hr.base_1_0_0.EmployeeTShirtSizes: Map<SSN, TShirtSizeType>" as org.acme.hr.base_1_0_0.EmployeeTShirtSizes {
+}
 class org.acme.hr.base_1_0_0.Address {
    + String street
    + String city
@@ -5808,6 +5824,18 @@ class org.acme.hr.base_1_0_0.Address {
    + String country
 }
 org.acme.hr.base_1_0_0.Address "1" *-- "1" org.acme.hr.base_1_0_0.State : state
+map "org.acme.hr_1_0_0.CompanyProperties: Map<String, String>" as org.acme.hr_1_0_0.CompanyProperties {
+}
+map "org.acme.hr_1_0_0.EmployeeLoginTimes: Map<String, Time>" as org.acme.hr_1_0_0.EmployeeLoginTimes {
+}
+map "org.acme.hr_1_0_0.EmployeeSocialSecurityNumbers: Map<String, SSN>" as org.acme.hr_1_0_0.EmployeeSocialSecurityNumbers {
+}
+map "org.acme.hr_1_0_0.NextOfKin: Map<KinName, KinTelephone>" as org.acme.hr_1_0_0.NextOfKin {
+}
+map "org.acme.hr_1_0_0.EmployeeProfiles: Map<String, Concept>" as org.acme.hr_1_0_0.EmployeeProfiles {
+}
+map "org.acme.hr_1_0_0.EmployeeDirectory: Map<SSN, Employee>" as org.acme.hr_1_0_0.EmployeeDirectory {
+}
 class org.acme.hr_1_0_0.Company {
    + String name
    + Address headquarters
@@ -9717,6 +9745,8 @@ class org.acme.hr.base_1_0_0.TShirtSizeType << (E,grey) >> {
    + LARGE
 }
 org.acme.hr.base_1_0_0.TShirtSizeType --|> concerto_1_0_0.Concept
+map "org.acme.hr.base_1_0_0.EmployeeTShirtSizes: Map<SSN, TShirtSizeType>" as org.acme.hr.base_1_0_0.EmployeeTShirtSizes {
+}
 class org.acme.hr.base_1_0_0.Address {
    + String street
    + String city
@@ -9726,6 +9756,18 @@ class org.acme.hr.base_1_0_0.Address {
 }
 org.acme.hr.base_1_0_0.Address "1" *-- "1" org.acme.hr.base_1_0_0.State : state
 org.acme.hr.base_1_0_0.Address --|> concerto_1_0_0.Concept
+map "org.acme.hr_1_0_0.CompanyProperties: Map<String, String>" as org.acme.hr_1_0_0.CompanyProperties {
+}
+map "org.acme.hr_1_0_0.EmployeeLoginTimes: Map<String, Time>" as org.acme.hr_1_0_0.EmployeeLoginTimes {
+}
+map "org.acme.hr_1_0_0.EmployeeSocialSecurityNumbers: Map<String, SSN>" as org.acme.hr_1_0_0.EmployeeSocialSecurityNumbers {
+}
+map "org.acme.hr_1_0_0.NextOfKin: Map<KinName, KinTelephone>" as org.acme.hr_1_0_0.NextOfKin {
+}
+map "org.acme.hr_1_0_0.EmployeeProfiles: Map<String, Concept>" as org.acme.hr_1_0_0.EmployeeProfiles {
+}
+map "org.acme.hr_1_0_0.EmployeeDirectory: Map<SSN, Employee>" as org.acme.hr_1_0_0.EmployeeDirectory {
+}
 class org.acme.hr_1_0_0.Company {
    + String name
    + Address headquarters
diff --git a/test/codegen/fromcto/plantuml/plantumlvisitor.js b/test/codegen/fromcto/plantuml/plantumlvisitor.js
index c97b0de5..34e2ddcd 100644
--- a/test/codegen/fromcto/plantuml/plantumlvisitor.js
+++ b/test/codegen/fromcto/plantuml/plantumlvisitor.js
@@ -25,6 +25,7 @@ const ModelManager = require('@accordproject/concerto-core').ModelManager;
 const AssetDeclaration = require('@accordproject/concerto-core').AssetDeclaration;
 const ParticipantDeclaration = require('@accordproject/concerto-core').ParticipantDeclaration;
 const ClassDeclaration = require('@accordproject/concerto-core').ClassDeclaration;
+const {MapDeclaration, MapKeyType, MapValueType } = require('@accordproject/concerto-core');
 const EnumDeclaration = require('@accordproject/concerto-core').EnumDeclaration;
 const EnumValueDeclaration = require('@accordproject/concerto-core').EnumValueDeclaration;
 const Field = require('@accordproject/concerto-core').Field;
@@ -440,6 +441,31 @@ describe('PlantUMLVisitor', function () {
         });
     });
 
+    describe('visitMapDeclaration', () => {
+        it('should write the map declaration for a map', () => {
+            let param = {
+                fileWriter: mockFileWriter
+            };
+
+            let mockMapDeclaration  = sinon.createStubInstance(MapDeclaration);
+            let mockMapKey          = sinon.createStubInstance(MapKeyType);
+            let mockMapValue        = sinon.createStubInstance(MapValueType);
+
+            mockMapDeclaration.getKey.returns(mockMapKey);
+            mockMapDeclaration.getValue.returns(mockMapValue);
+            mockMapKey.getType.returns('String');
+            mockMapValue.getType.returns('String');
+
+            mockMapDeclaration.getFullyQualifiedName.returns('org.acme.NextOfKin');
+
+            plantUMLvisitor.visitMapDeclaration(mockMapDeclaration, param);
+
+            param.fileWriter.writeLine.callCount.should.deep.equal(2);
+            param.fileWriter.writeLine.getCall(0).args.should.deep.equal([0, 'map "org.acme.NextOfKin: Map<String, String>" as org.acme.NextOfKin {']);
+            param.fileWriter.writeLine.getCall(1).args.should.deep.equal([0, '}']);
+        });
+    });
+
     describe('visitClassDeclaration', () => {
         it('should write the class declaration for a class', () => {
             let acceptSpy = sinon.spy();