diff --git a/src/main/java/ntnu/idatt2016/v233/SmartMat/entity/group/Group.java b/src/main/java/ntnu/idatt2016/v233/SmartMat/entity/group/Group.java
index 64c0adb41ac5e017c044a20e92485a37ec6cf1cd..3bb7c5418829964c5f21656cd39b1d74ae901464 100644
--- a/src/main/java/ntnu/idatt2016/v233/SmartMat/entity/group/Group.java
+++ b/src/main/java/ntnu/idatt2016/v233/SmartMat/entity/group/Group.java
@@ -42,16 +42,18 @@ public class Group {
     @Column(name = "group_name")
     String groupName;
 
-    @OneToMany(mappedBy = "group")
-    @JsonIgnoreProperties({"password", "group"})
-    @OnDelete(action = OnDeleteAction.CASCADE)
+    @ManyToMany
+    @JoinTable(name = "users_groups",
+            joinColumns = @JoinColumn(name = "group_id"),
+            inverseJoinColumns = @JoinColumn(name = "username"))
+    @JsonIgnoreProperties({"groups"})
     private List<User> users;
 
 
     @ManyToMany
     @JoinTable(name = "group_achievement",
             joinColumns = @JoinColumn(name = "group_id"),
-            inverseJoinColumns = @JoinColumn(name = "achievement_name"))
+            inverseJoinColumns = @JoinColumn(name = "username"))
     @JsonIgnoreProperties({"groups"})
     private List<Achievement> achievements;
 
diff --git a/src/main/java/ntnu/idatt2016/v233/SmartMat/entity/user/User.java b/src/main/java/ntnu/idatt2016/v233/SmartMat/entity/user/User.java
index 12682036959cb04b7ec7c01e1d1c09d2636db337..35e86730ba3ab6f3a73445c0967eaffb61327876 100644
--- a/src/main/java/ntnu/idatt2016/v233/SmartMat/entity/user/User.java
+++ b/src/main/java/ntnu/idatt2016/v233/SmartMat/entity/user/User.java
@@ -8,6 +8,7 @@ import lombok.Builder;
 import lombok.Data;
 import lombok.NoArgsConstructor;
 import ntnu.idatt2016.v233.SmartMat.dto.enums.Authority;
+import ntnu.idatt2016.v233.SmartMat.entity.group.Achievement;
 import ntnu.idatt2016.v233.SmartMat.entity.group.Group;
 import org.springframework.security.core.GrantedAuthority;
 import org.springframework.security.core.authority.SimpleGrantedAuthority;
@@ -41,10 +42,10 @@ public class User implements UserDetails {
     @Column(name = "enabled")
     private boolean enabled;
 
-    @Column
+    @Column(name = "email")
     private String email;
 
-    @Column
+    @Column (name = "first_name")
     private String firstName;
 
     @Column(name = "last_name")
@@ -53,6 +54,13 @@ public class User implements UserDetails {
     @Column(name = "birthdate")
     private Date dateOfBirth;
 
+    @ManyToMany
+    @JoinTable(name = "users_groups",
+            joinColumns = @JoinColumn(name = "username"),
+            inverseJoinColumns = @JoinColumn(name = "group_id"))
+    @JsonIgnoreProperties({"users"})
+    private List<Group> groups;
+
     @Enumerated(EnumType.STRING)
     private Authority authority;