diff --git a/src/models/entities/Address.ts b/src/models/entities/Address.ts
index afa10da..561808f 100644
--- a/src/models/entities/Address.ts
+++ b/src/models/entities/Address.ts
@@ -7,7 +7,7 @@ import {
 } from "class-validator";
 import { Column, Entity, OneToMany, PrimaryGeneratedColumn } from "typeorm";
 import { config } from '../../config';
-import { Participant } from "./Participant";
+import { IAddressUser } from './IAddressUser';
 
 /**
  * Defines the Address entity.
@@ -78,13 +78,6 @@ export class Address {
   /**
    * Used to link the address to participants.
    */
-  @OneToMany(() => Participant, participant => participant.address, { nullable: true })
-  participants: Participant[];
-
-  //TODO: #68
-  // /**
-  //  * Used to link the address to runner groups.
-  //  */
-  // @OneToMany(() => RunnerOrganisation, group => group.address, { nullable: true })
-  // groups: RunnerOrganisation[];
+  @OneToMany(() => IAddressUser, addressUser => addressUser.address, { nullable: true })
+  addressUsers: IAddressUser[];
 }
diff --git a/src/models/entities/GroupContact.ts b/src/models/entities/GroupContact.ts
index f524863..4dbcc5e 100644
--- a/src/models/entities/GroupContact.ts
+++ b/src/models/entities/GroupContact.ts
@@ -10,6 +10,7 @@ import {
 import { Column, Entity, ManyToOne, OneToMany, PrimaryGeneratedColumn } from "typeorm";
 import { config } from '../../config';
 import { Address } from "./Address";
+import { IAddressUser } from './IAddressUser';
 import { RunnerGroup } from "./RunnerGroup";
 
 /**
@@ -17,7 +18,7 @@ import { RunnerGroup } from "./RunnerGroup";
  * Mainly it's own class to reduce duplicate code and enable contact's to be associated with multiple groups.
 */
 @Entity()
-export class GroupContact {
+export class GroupContact implements IAddressUser {
   /**
    * Autogenerated unique id (primary key).
    */
@@ -54,7 +55,7 @@ export class GroupContact {
    * This is a address object to prevent any formatting differences.
    */
   @IsOptional()
-  @ManyToOne(() => Address, address => address.participants, { nullable: true })
+  @ManyToOne(() => Address, address => address.addressUsers, { nullable: true })
   address?: Address;
 
   /**
diff --git a/src/models/entities/IAddressUser.ts b/src/models/entities/IAddressUser.ts
new file mode 100644
index 0000000..425f4e3
--- /dev/null
+++ b/src/models/entities/IAddressUser.ts
@@ -0,0 +1,11 @@
+import { Entity, ManyToOne, PrimaryColumn } from 'typeorm';
+import { Address } from './Address';
+
+@Entity()
+export abstract class IAddressUser {
+    @PrimaryColumn()
+    id: number;
+
+    @ManyToOne(() => Address, address => address.addressUsers, { nullable: true })
+    address?: Address
+}
diff --git a/src/models/entities/Participant.ts b/src/models/entities/Participant.ts
index 19af17e..de13b5f 100644
--- a/src/models/entities/Participant.ts
+++ b/src/models/entities/Participant.ts
@@ -10,6 +10,7 @@ import {
 import { Column, Entity, ManyToOne, PrimaryGeneratedColumn, TableInheritance } from "typeorm";
 import { config } from '../../config';
 import { Address } from "./Address";
+import { IAddressUser } from './IAddressUser';
 
 /**
  * Defines the Participant entity.
@@ -17,7 +18,7 @@ import { Address } from "./Address";
 */
 @Entity()
 @TableInheritance({ column: { name: "type", type: "varchar" } })
-export abstract class Participant {
+export abstract class Participant implements IAddressUser {
   /**
    * Autogenerated unique id (primary key).
    */
@@ -53,7 +54,7 @@ export abstract class Participant {
    * The participant's address.
    * This is a address object to prevent any formatting differences.
    */
-  @ManyToOne(() => Address, address => address.participants, { nullable: true })
+  @ManyToOne(() => Address, address => address.addressUsers, { nullable: true })
   address?: Address;
 
   /**
diff --git a/src/models/entities/RunnerOrganisation.ts b/src/models/entities/RunnerOrganisation.ts
index 7110b09..f0f8c78 100644
--- a/src/models/entities/RunnerOrganisation.ts
+++ b/src/models/entities/RunnerOrganisation.ts
@@ -1,5 +1,7 @@
-import { IsInt } from "class-validator";
-import { ChildEntity, OneToMany } from "typeorm";
+import { IsInt, IsOptional } from "class-validator";
+import { ChildEntity, ManyToOne, OneToMany } from "typeorm";
+import { Address } from './Address';
+import { IAddressUser } from './IAddressUser';
 import { Runner } from './Runner';
 import { RunnerGroup } from "./RunnerGroup";
 import { RunnerTeam } from "./RunnerTeam";
@@ -9,14 +11,14 @@ import { RunnerTeam } from "./RunnerTeam";
  * This usually is a school, club or company.
 */
 @ChildEntity()
-export class RunnerOrganisation extends RunnerGroup {
+export class RunnerOrganisation extends RunnerGroup implements IAddressUser {
 
-  // /**
-  //  * The organisations's address.
-  //  */
-  // @IsOptional()
-  // @ManyToOne(() => Address, address => address.groups, { nullable: true })
-  // address?: Address;
+  /**
+   * The organisations's address.
+   */
+  @IsOptional()
+  @ManyToOne(() => Address, address => address.addressUsers, { nullable: true })
+  address?: Address;
 
   /**
    * The organisation's teams.