diff --git a/src/models/Runner.ts b/src/models/Runner.ts
index 49ce643..3db90fc 100644
--- a/src/models/Runner.ts
+++ b/src/models/Runner.ts
@@ -3,6 +3,7 @@ import { IsNotEmpty,} from "class-validator";
 import { Participant } from "./Participant";
 import { RunnerGroup } from "./RunnerGroup";
 import { DistanceDonation } from "./DistanceDonation";
+import { RunnerCard } from "./RunnerCard";
 
 /**
  * Defines a runner.
@@ -22,4 +23,10 @@ export class Runner extends Participant {
    */
   @OneToMany(() => DistanceDonation, distanceDonation => distanceDonation.runner)
   distanceDonations: DistanceDonation[];
+
+  /**
+   * Used to link runners to cards.
+   */
+  @OneToMany(() => RunnerCard, card => card.runner)
+  cards: RunnerCard[];
 }
diff --git a/src/models/RunnerCard.ts b/src/models/RunnerCard.ts
index 09b3746..151f58c 100644
--- a/src/models/RunnerCard.ts
+++ b/src/models/RunnerCard.ts
@@ -1,4 +1,4 @@
-import { Entity, PrimaryGeneratedColumn, Column } from "typeorm";
+import { Entity, PrimaryGeneratedColumn, Column, ManyToOne } from "typeorm";
 import {
   IsBoolean,
   IsInt,
@@ -26,7 +26,7 @@ export class RunnerCard {
    */
   @Column()
   @IsOptional()
-  //TODO: Relation
+  @ManyToOne(() => Runner, runner => runner.cards)
   runner: Runner;
 
   /**