diff --git a/src/app/[locale]/admin/users/UserForm.tsx b/src/app/[locale]/admin/users/UserForm.tsx
index 5e7ab78..9876410 100644
--- a/src/app/[locale]/admin/users/UserForm.tsx
+++ b/src/app/[locale]/admin/users/UserForm.tsx
@@ -18,7 +18,8 @@ import { useI18n, useCurrentLocale } from '@/locales/client';
 import { registerUser, updateUser } from '@/app/actions/user';
 
 const formSchema = z.object({
-  name: z.string().min(2, "Name must be at least 2 characters."),
+  name: z.string().min(2, "Full name must be at least 2 characters."),
+  nickname: z.string().optional(),
   email: z.string().email("Invalid email address."),
   role: z.enum(['User', 'Admin']),
 });
@@ -40,6 +41,7 @@ export default function UserForm({ initialData, isEditMode = false }: UserFormPr
     resolver: zodResolver(formSchema),
     defaultValues: {
       name: initialData?.name || '',
+      nickname: initialData?.nickname || '',
       email: initialData?.email || '',
       role: initialData?.role || 'User',
     },
@@ -85,7 +87,20 @@ export default function UserForm({ initialData, isEditMode = false }: UserFormPr
               name="name"
               render={({ field }) => (
                 <FormItem>
-                  <FormLabel>{t('admin.users.form_name_label')}</FormLabel>
+                  <FormLabel>{t('admin.users.form_full_name_label')}</FormLabel>
+                  <FormControl>
+                    <Input placeholder="e.g., John Doe" {...field} disabled={isSubmitting} />
+                  </FormControl>
+                  <FormMessage />
+                </FormItem>
+              )}
+            />
+             <FormField
+              control={form.control}
+              name="nickname"
+              render={({ field }) => (
+                <FormItem>
+                  <FormLabel>{t('admin.users.form_nickname_label')}</FormLabel>
                   <FormControl>
                     <Input placeholder="e.g., Johnny" {...field} disabled={isSubmitting} />
                   </FormControl>
diff --git a/src/app/[locale]/admin/users/page.tsx b/src/app/[locale]/admin/users/page.tsx
index 3ff938a..5fa3b60 100644
--- a/src/app/[locale]/admin/users/page.tsx
+++ b/src/app/[locale]/admin/users/page.tsx
@@ -102,7 +102,8 @@ export default function AdminUserManagementPage() {
             <Table>
               <TableHeader>
                 <TableRow>
-                  <TableHead>{t('admin.users.table_header_name')}</TableHead>
+                  <TableHead>{t('admin.users.table_header_full_name')}</TableHead>
+                  <TableHead>{t('admin.users.table_header_nickname')}</TableHead>
                   <TableHead>{t('admin.users.table_header_email')}</TableHead>
                   <TableHead>{t('admin.users.table_header_role')}</TableHead>
                   <TableHead className="text-right">{t('admin.users.table_header_actions')}</TableHead>
@@ -112,6 +113,7 @@ export default function AdminUserManagementPage() {
                 {users.map((user) => (
                   <TableRow key={user.id}>
                     <TableCell className="font-medium">{user.name}</TableCell>
+                    <TableCell>{user.nickname}</TableCell>
                     <TableCell>{user.email}</TableCell>
                     <TableCell>{user.role}</TableCell>
                     <TableCell className="text-right space-x-2">
diff --git a/src/app/[locale]/dashboard/profile/page.tsx b/src/app/[locale]/dashboard/profile/page.tsx
index 515dd95..39968ec 100644
--- a/src/app/[locale]/dashboard/profile/page.tsx
+++ b/src/app/[locale]/dashboard/profile/page.tsx
@@ -15,6 +15,7 @@ import { Select, SelectContent, SelectItem, SelectTrigger, SelectValue } from '@
 
 const mockUserProfile = {
   name: 'Alice Wonderland',
+  nickname: 'Alice',
   email: 'alice@example.com',
   avatarUrl: 'https://placehold.co/100x100.png?text=AW',
   bio: "Lover of imaginative play and sharing joy. I have a collection of classic storybooks and dress-up costumes.",
@@ -29,6 +30,7 @@ export default function ProfilePage() {
   const changeLocale = useChangeLocale();
 
   const [name, setName] = useState(mockUserProfile.name);
+  const [nickname, setNickname] = useState(mockUserProfile.nickname);
   const [email, setEmail] = useState(mockUserProfile.email); 
   const [avatarUrl, setAvatarUrl] = useState(mockUserProfile.avatarUrl);
   const [bio, setBio] = useState(mockUserProfile.bio);
@@ -52,7 +54,7 @@ export default function ProfilePage() {
     e.preventDefault();
     setIsLoading(true);
     await new Promise(resolve => setTimeout(resolve, 1000));
-    console.log("Updating profile:", { name, avatarUrl, bio, phone, location });
+    console.log("Updating profile:", { name, nickname, avatarUrl, bio, phone, location });
     toast({ title: t('dashboard.profile.save_button'), description: "Your profile information has been saved." }); 
     setIsLoading(false);
   };
@@ -117,14 +119,19 @@ export default function ProfilePage() {
             <div className="grid grid-cols-1 md:grid-cols-2 gap-6">
               <div className="space-y-1">
                 <Label htmlFor="name">{t('dashboard.profile.full_name_label')}</Label>
-                <Input id="name" value={name} onChange={(e) => setName(e.target.value)} placeholder="Your Nickname" disabled={isLoading} />
+                <Input id="name" value={name} onChange={(e) => setName(e.target.value)} placeholder="Your Full Name" required disabled={isLoading} />
               </div>
               <div className="space-y-1">
-                <Label htmlFor="email">{t('dashboard.profile.email_label')}</Label>
-                <Input id="email" type="email" value={email} readOnly disabled className="bg-muted/50 cursor-not-allowed" />
+                <Label htmlFor="nickname">{t('dashboard.profile.nickname_label')}</Label>
+                <Input id="nickname" value={nickname} onChange={(e) => setNickname(e.target.value)} placeholder="Your Nickname" disabled={isLoading} />
               </div>
             </div>
             
+            <div className="space-y-1">
+              <Label htmlFor="email">{t('dashboard.profile.email_label')}</Label>
+              <Input id="email" type="email" value={email} readOnly disabled className="bg-muted/50 cursor-not-allowed" />
+            </div>
+
             <div className="space-y-1">
               <Label htmlFor="bio">{t('dashboard.profile.bio_label')}</Label>
               <Textarea id="bio" value={bio} onChange={(e) => setBio(e.target.value)} placeholder="Tell us a bit about yourself and your toys..." rows={3} disabled={isLoading}/>
diff --git a/src/app/[locale]/register/page.tsx b/src/app/[locale]/register/page.tsx
index 75e0ada..85651fd 100644
--- a/src/app/[locale]/register/page.tsx
+++ b/src/app/[locale]/register/page.tsx
@@ -20,6 +20,7 @@ export default function RegisterPage() {
   const locale = useCurrentLocale();
 
   const [name, setName] = useState('');
+  const [nickname, setNickname] = useState('');
   const [email, setEmail] = useState('');
   const [password, setPassword] = useState('');
   const [confirmPassword, setConfirmPassword] = useState('');
@@ -39,7 +40,7 @@ export default function RegisterPage() {
       return;
     }
 
-    const result = await registerUser({ name, email });
+    const result = await registerUser({ name, nickname, email });
 
     if (result.success && result.user) {
       // Mock login after successful registration
@@ -85,16 +86,27 @@ export default function RegisterPage() {
         <CardContent>
           <form onSubmit={handleSubmit} className="space-y-6">
             <div className="space-y-2">
-              <Label htmlFor="name">{t('register.name_label')}</Label>
+              <Label htmlFor="name">{t('register.full_name_label')}</Label>
               <Input
                 id="name"
                 type="text"
-                placeholder="e.g., Johnny"
+                placeholder="e.g., John Doe"
                 value={name}
                 onChange={(e) => setName(e.target.value)}
                 required
                 disabled={isLoading}
               />
+            </div>
+             <div className="space-y-2">
+              <Label htmlFor="nickname">{t('register.nickname_label')}</Label>
+              <Input
+                id="nickname"
+                type="text"
+                placeholder="e.g., Johnny"
+                value={nickname}
+                onChange={(e) => setNickname(e.target.value)}
+                disabled={isLoading}
+              />
             </div>
             <div className="space-y-2">
               <Label htmlFor="email">{t('login.email_label')}</Label>
diff --git a/src/app/actions/user.ts b/src/app/actions/user.ts
index 035d628..b52d5c3 100644
--- a/src/app/actions/user.ts
+++ b/src/app/actions/user.ts
@@ -13,11 +13,11 @@ interface RegisterUserResult {
   user?: User;
 }
 
-export async function registerUser(data: { name: string; email: string; password?: string, role?: 'Admin' | 'User' }): Promise<RegisterUserResult> {
-  const { name, email, role = 'User' } = data;
+export async function registerUser(data: { name: string; nickname?: string; email: string; password?: string, role?: 'Admin' | 'User' }): Promise<RegisterUserResult> {
+  const { name, nickname, email, role = 'User' } = data;
 
   if (!name || !email) {
-    return { success: false, message: 'Name and email are required.' };
+    return { success: false, message: 'Full name and email are required.' };
   }
 
   try {
@@ -29,6 +29,7 @@ export async function registerUser(data: { name: string; email: string; password
     const newUser: User = {
       id: `user-${randomUUID()}`,
       name,
+      nickname,
       email,
       role: role,
       avatarUrl: '', 
@@ -36,7 +37,7 @@ export async function registerUser(data: { name: string; email: string; password
     };
 
     const stmt = db.prepare(
-      'INSERT INTO users (id, name, email, role, avatarUrl, bio) VALUES (@id, @name, @email, @role, @avatarUrl, @bio)'
+      'INSERT INTO users (id, name, nickname, email, role, avatarUrl, bio) VALUES (@id, @name, @nickname, @email, @role, @avatarUrl, @bio)'
     );
 
     stmt.run(newUser);
@@ -67,12 +68,13 @@ export async function updateUser(user: User): Promise<UpdateUserResult> {
     }
 
     const stmt = db.prepare(
-      'UPDATE users SET name = @name, email = @email, role = @role, avatarUrl = @avatarUrl, bio = @bio WHERE id = @id'
+      'UPDATE users SET name = @name, nickname = @nickname, email = @email, role = @role, avatarUrl = @avatarUrl, bio = @bio WHERE id = @id'
     );
     
     stmt.run({
         id: user.id,
         name: user.name,
+        nickname: user.nickname ?? null,
         email: user.email,
         role: user.role,
         avatarUrl: user.avatarUrl ?? '',
diff --git a/src/data/operations.ts b/src/data/operations.ts
index 2a2c2c9..37e6384 100644
--- a/src/data/operations.ts
+++ b/src/data/operations.ts
@@ -57,7 +57,7 @@ export function getOwnerProfile(ownerId: string) {
 // --- USER OPERATIONS ---
 
 export function getAllUsers(): User[] {
-  const stmt = db.prepare('SELECT id, name, email, role, avatarUrl, bio FROM users');
+  const stmt = db.prepare('SELECT id, name, nickname, email, role, avatarUrl, bio FROM users');
   return stmt.all() as User[];
 }
 
diff --git a/src/lib/db.ts b/src/lib/db.ts
index 388769c..2d28d87 100644
--- a/src/lib/db.ts
+++ b/src/lib/db.ts
@@ -22,6 +22,7 @@ function initDb() {
     CREATE TABLE IF NOT EXISTS users (
       id TEXT PRIMARY KEY,
       name TEXT NOT NULL,
+      nickname TEXT,
       email TEXT NOT NULL UNIQUE,
       role TEXT,
       avatarUrl TEXT,
@@ -50,8 +51,8 @@ function initDb() {
   // Use INSERT OR IGNORE to only add data if the primary key doesn't exist.
   // This prevents errors on subsequent runs and adds missing users/toys without overwriting.
   const insertUser = db.prepare(`
-    INSERT OR IGNORE INTO users (id, name, email, role, avatarUrl, bio) 
-    VALUES (@id, @name, @email, @role, @avatarUrl, @bio)
+    INSERT OR IGNORE INTO users (id, name, nickname, email, role, avatarUrl, bio) 
+    VALUES (@id, @name, @nickname, @email, @role, @avatarUrl, @bio)
   `);
   
   const insertToy = db.prepare(`
@@ -64,6 +65,7 @@ function initDb() {
         insertUser.run({
             id: user.id,
             name: user.name,
+            nickname: user.nickname ?? null,
             email: user.email,
             role: user.role ?? 'User',
             avatarUrl: user.avatarUrl ?? null,
diff --git a/src/lib/mockData.ts b/src/lib/mockData.ts
index 942cf2f..4c662b0 100644
--- a/src/lib/mockData.ts
+++ b/src/lib/mockData.ts
@@ -5,13 +5,13 @@ import { addDays, formatISO, subDays } from 'date-fns';
 const today = new Date();
 
 export const rawUsers: User[] = [
-  { id: 'user1', name: 'Alice Wonderland', email: 'user@example.com', role: 'Admin', avatarUrl: 'https://placehold.co/100x100.png?text=AW', bio: "Lover of imaginative play and sharing joy. I have a collection of classic storybooks and dress-up costumes that my kids have outgrown but still have lots of life left in them!" },
-  { id: 'user2', name: 'Bob The Builder', email: 'user2@example.com', role: 'User', avatarUrl: 'https://placehold.co/100x100.png?text=BT', bio: "Can we fix it? Yes, we can! Sharing my collection of construction toys, tools, and playsets. Always happy to help another budding builder." },
-  { id: 'user3', name: 'Carol Danvers', email: 'user3@example.com', role: 'User', avatarUrl: 'https://placehold.co/100x100.png?text=CD', bio: "Higher, further, faster. Sharing toys that inspire adventure, courage, and exploration. My collection includes superhero action figures and space-themed playsets." },
-  { id: 'user4', name: 'Charlie Brown', email: 'user4@example.com', role: 'User' },
-  { id: 'user5', name: 'Diana Prince', email: 'user5@example.com', role: 'User' },
-  { id: 'user6', name: 'Edward Nigma', email: 'user6@example.com', role: 'User' },
-  { id: 'admin-main', name: 'Main Admin', email: 'admin@example.com', role: 'Admin' },
+  { id: 'user1', name: 'Alice Wonderland', nickname: 'Alice', email: 'user@example.com', role: 'Admin', avatarUrl: 'https://placehold.co/100x100.png?text=AW', bio: "Lover of imaginative play and sharing joy. I have a collection of classic storybooks and dress-up costumes that my kids have outgrown but still have lots of life left in them!" },
+  { id: 'user2', name: 'Bob The Builder', nickname: 'Bob', email: 'user2@example.com', role: 'User', avatarUrl: 'https://placehold.co/100x100.png?text=BT', bio: "Can we fix it? Yes, we can! Sharing my collection of construction toys, tools, and playsets. Always happy to help another budding builder." },
+  { id: 'user3', name: 'Carol Danvers', nickname: 'Captain Marvel', email: 'user3@example.com', role: 'User', avatarUrl: 'https://placehold.co/100x100.png?text=CD', bio: "Higher, further, faster. Sharing toys that inspire adventure, courage, and exploration. My collection includes superhero action figures and space-themed playsets." },
+  { id: 'user4', name: 'Charlie Brown', nickname: 'Chuck', email: 'user4@example.com', role: 'User' },
+  { id: 'user5', name: 'Diana Prince', nickname: 'Wonder Woman', email: 'user5@example.com', role: 'User' },
+  { id: 'user6', name: 'Edward Nigma', nickname: 'Riddler', email: 'user6@example.com', role: 'User' },
+  { id: 'admin-main', name: 'Main Admin', nickname: 'Head Honcho', email: 'admin@example.com', role: 'Admin' },
 ];
 
 export const rawToys: Omit<Toy, 'ownerName' | 'dataAiHint'>[] = [
diff --git a/src/locales/en.ts b/src/locales/en.ts
index ad76f3c..331d7a4 100644
--- a/src/locales/en.ts
+++ b/src/locales/en.ts
@@ -31,7 +31,8 @@ export default {
   'login.invalid_credentials_toast_user': 'Invalid email or password. (Hint: user@example.com / password or admin@example.com / passwordadmin)',
   'register.create_account': 'Create Your Account',
   'register.description': 'Join ToyShare and start sharing the fun!',
-  'register.name_label': 'Nickname',
+  'register.full_name_label': 'Full Name',
+  'register.nickname_label': 'Nickname (Optional)',
   'register.confirm_password_label': 'Confirm Password',
   'register.submit_button': 'Create Account',
   'register.loading_button': 'Registering...',
@@ -96,7 +97,8 @@ export default {
   'dashboard.profile.personal_info_title': 'Personal Information',
   'dashboard.profile.personal_info_description': 'Update your publicly visible profile information.',
   'dashboard.profile.avatar_url_label': 'Avatar URL',
-  'dashboard.profile.full_name_label': 'Nickname',
+  'dashboard.profile.full_name_label': 'Full Name',
+  'dashboard.profile.nickname_label': 'Nickname',
   'dashboard.profile.email_label': 'Email Address (Read-only)',
   'dashboard.profile.bio_label': 'Bio',
   'dashboard.profile.phone_label': 'Phone Number',
@@ -230,7 +232,8 @@ export default {
   'admin.users.description': 'View and manage user accounts and permissions.',
   'admin.users.add_user_button': 'Add New User',
   'admin.users.back_to_users_button': 'Back to User List',
-  'admin.users.table_header_name': 'Nickname',
+  'admin.users.table_header_full_name': 'Full Name',
+  'admin.users.table_header_nickname': 'Nickname',
   'admin.users.table_header_email': 'Email',
   'admin.users.table_header_role': 'Role',
   'admin.users.table_header_actions': 'Actions',
@@ -241,7 +244,8 @@ export default {
   'admin.users.add_user_description': 'Create a new user account and assign a role.',
   'admin.users.edit_user_title': 'Edit User',
   'admin.users.edit_user_description': "Update the user's details and role.",
-  'admin.users.form_name_label': 'Nickname',
+  'admin.users.form_full_name_label': 'Full Name',
+  'admin.users.form_nickname_label': 'Nickname (Optional)',
   'admin.users.form_email_label': 'Email Address',
   'admin.users.form_role_label': 'Role',
   'admin.users.form_role_user': 'User',
diff --git a/src/locales/zh-TW.ts b/src/locales/zh-TW.ts
index ca565e8..4d85716 100644
--- a/src/locales/zh-TW.ts
+++ b/src/locales/zh-TW.ts
@@ -31,7 +31,8 @@ export default {
   'login.invalid_credentials_toast_user': '無效的電子郵件或密碼。(提示: user@example.com / password 或 admin@example.com / passwordadmin)',
   'register.create_account': '建立您的帳戶',
   'register.description': '加入 ToyShare，開始分享樂趣！',
-  'register.name_label': '暱稱',
+  'register.full_name_label': '全名',
+  'register.nickname_label': '暱稱 (選填)',
   'register.confirm_password_label': '確認密碼',
   'register.submit_button': '建立帳戶',
   'register.loading_button': '註冊中...',
@@ -96,7 +97,8 @@ export default {
   'dashboard.profile.personal_info_title': '個人資訊',
   'dashboard.profile.personal_info_description': '更新您公開顯示的個人資料資訊。',
   'dashboard.profile.avatar_url_label': '頭像 URL',
-  'dashboard.profile.full_name_label': '暱稱',
+  'dashboard.profile.full_name_label': '全名',
+  'dashboard.profile.nickname_label': '暱稱',
   'dashboard.profile.email_label': '電子郵件地址 (唯讀)',
   'dashboard.profile.bio_label': '簡介',
   'dashboard.profile.phone_label': '電話號碼',
@@ -230,7 +232,8 @@ export default {
   'admin.users.description': '查看和管理使用者帳戶及權限。',
   'admin.users.add_user_button': '新增使用者',
   'admin.users.back_to_users_button': '返回使用者列表',
-  'admin.users.table_header_name': '暱稱',
+  'admin.users.table_header_full_name': '全名',
+  'admin.users.table_header_nickname': '暱稱',
   'admin.users.table_header_email': '電子郵件',
   'admin.users.table_header_role': '角色',
   'admin.users.table_header_actions': '操作',
@@ -241,7 +244,8 @@ export default {
   'admin.users.add_user_description': '建立一個新的使用者帳戶並分配角色。',
   'admin.users.edit_user_title': '編輯使用者',
   'admin.users.edit_user_description': '更新使用者的詳細資訊和角色。',
-  'admin.users.form_name_label': '暱稱',
+  'admin.users.form_full_name_label': '全名',
+  'admin.users.form_nickname_label': '暱稱 (選填)',
   'admin.users.form_email_label': '電子郵件地址',
   'admin.users.form_role_label': '角色',
   'admin.users.form_role_user': '使用者',
diff --git a/src/types/index.ts b/src/types/index.ts
index c1aa5b1..68ce1b3 100644
--- a/src/types/index.ts
+++ b/src/types/index.ts
@@ -23,7 +23,8 @@ export interface Toy {
 
 export interface User {
   id: string;
-  name: string;
+  name: string; // This is now Full Name
+  nickname?: string;
   email: string;
   role?: 'Admin' | 'User';
   avatarUrl?: string;