diff --git a/src/views/Settings.vue b/src/views/Settings.vue
index d858b53..7a92fea 100644
--- a/src/views/Settings.vue
+++ b/src/views/Settings.vue
@@ -1,132 +1,170 @@
 <template>
-  <div class="p-6 max-w-xl">
-    <h1 class="text-[1.5rem] font-medium text-text-primary mb-8">Settings</h1>
+  <div class="flex h-full">
+    <!-- Sidebar -->
+    <aside class="w-44 bg-bg-surface border-r border-border-subtle shrink-0 p-3">
+      <h1 class="text-[0.8125rem] font-medium text-text-tertiary uppercase tracking-[0.08em] px-2 mb-3">Settings</h1>
+      <nav class="flex flex-col gap-0.5">
+        <button
+          v-for="tab in tabs"
+          :key="tab.id"
+          @click="activeTab = tab.id"
+          class="relative flex items-center gap-2.5 px-2.5 py-2 rounded text-[0.8125rem] transition-colors duration-150"
+          :class="activeTab === tab.id
+            ? 'bg-bg-elevated text-text-primary'
+            : 'text-text-secondary hover:bg-bg-elevated hover:text-text-primary'"
+        >
+          <!-- Active indicator -->
+          <div
+            v-if="activeTab === tab.id"
+            class="absolute left-0 top-1.5 bottom-1.5 w-[2px] rounded-full bg-accent"
+          />
+          <component :is="tab.icon" class="w-4 h-4 shrink-0" :stroke-width="1.5" />
+          {{ tab.label }}
+        </button>
+      </nav>
+    </aside>
 
-    <!-- 1. Appearance — most frequently adjusted -->
-    <section class="bg-bg-surface rounded-lg p-5 mb-4">
-      <h2 class="text-xs text-text-tertiary uppercase tracking-[0.08em] font-medium mb-4">Appearance</h2>
-      <div class="flex items-center justify-between">
-        <p class="text-[0.8125rem] text-text-primary">UI Scale</p>
-        <div class="flex items-center gap-2">
-          <button
-            @click="decreaseZoom"
-            class="w-8 h-8 flex items-center justify-center border border-border-visible rounded text-text-secondary hover:text-text-primary hover:bg-bg-elevated transition-colors disabled:opacity-40 disabled:cursor-not-allowed"
-            :disabled="zoomLevel <= 80"
-          >
-            <Minus class="w-3.5 h-3.5" />
-          </button>
-          <span class="w-12 text-center text-sm font-mono text-text-primary">{{ zoomLevel }}%</span>
-          <button
-            @click="increaseZoom"
-            class="w-8 h-8 flex items-center justify-center border border-border-visible rounded text-text-secondary hover:text-text-primary hover:bg-bg-elevated transition-colors disabled:opacity-40 disabled:cursor-not-allowed"
-            :disabled="zoomLevel >= 150"
-          >
-            <Plus class="w-3.5 h-3.5" />
-          </button>
-        </div>
-      </div>
-    </section>
+    <!-- Content pane -->
+    <div class="flex-1 p-6 overflow-y-auto">
+      <!-- General -->
+      <div v-if="activeTab === 'general'">
+        <h2 class="text-[1.125rem] font-medium text-text-primary mb-6">General</h2>
 
-    <!-- 2. Timer — behavioral settings -->
-    <section class="bg-bg-surface rounded-lg p-5 mb-4">
-      <h2 class="text-xs text-text-tertiary uppercase tracking-[0.08em] font-medium mb-4">Timer</h2>
-      <div class="space-y-4">
-        <!-- Idle Detection toggle -->
         <div class="flex items-center justify-between">
-          <p class="text-[0.8125rem] text-text-primary">Idle Detection</p>
-          <button
-            @click="toggleIdleDetection"
-            :class="[
-              'relative inline-flex h-5 w-9 items-center rounded-full transition-colors duration-150',
-              idleDetection ? 'bg-status-running' : 'bg-bg-elevated'
-            ]"
-          >
-            <span
-              :class="[
-                'inline-block h-3.5 w-3.5 transform rounded-full bg-text-primary transition-transform duration-150',
-                idleDetection ? 'translate-x-[18px]' : 'translate-x-[3px]'
-              ]"
-            />
-          </button>
-        </div>
-
-        <!-- Reminder Interval — indented child of idle detection, progressive disclosure -->
-        <div
-          v-if="idleDetection"
-          class="flex items-center justify-between pl-4 border-l-2 border-border-subtle ml-1"
-        >
           <div>
-            <p class="text-[0.8125rem] text-text-primary">Reminder Interval</p>
-            <p class="text-[0.6875rem] text-text-tertiary mt-0.5">Minutes between reminders while running</p>
+            <p class="text-[0.8125rem] text-text-primary">UI Scale</p>
+            <p class="text-[0.6875rem] text-text-tertiary mt-0.5">Adjust the interface zoom level</p>
+          </div>
+          <div class="flex items-center gap-2">
+            <button
+              @click="decreaseZoom"
+              class="w-8 h-8 flex items-center justify-center border border-border-visible rounded text-text-secondary hover:text-text-primary hover:bg-bg-elevated transition-colors disabled:opacity-40 disabled:cursor-not-allowed"
+              :disabled="zoomLevel <= 80"
+            >
+              <Minus class="w-3.5 h-3.5" />
+            </button>
+            <span class="w-12 text-center text-sm font-mono text-text-primary">{{ zoomLevel }}%</span>
+            <button
+              @click="increaseZoom"
+              class="w-8 h-8 flex items-center justify-center border border-border-visible rounded text-text-secondary hover:text-text-primary hover:bg-bg-elevated transition-colors disabled:opacity-40 disabled:cursor-not-allowed"
+              :disabled="zoomLevel >= 150"
+            >
+              <Plus class="w-3.5 h-3.5" />
+            </button>
           </div>
-          <input
-            v-model.number="reminderInterval"
-            type="number"
-            min="0"
-            max="120"
-            class="w-20 px-3 py-1.5 bg-bg-inset border border-border-subtle rounded text-[0.8125rem] text-text-primary text-right font-mono focus:outline-none focus:border-border-visible"
-            @change="saveSettings"
-          />
         </div>
       </div>
-    </section>
 
-    <!-- 3. Billing — less frequently changed -->
-    <section class="bg-bg-surface rounded-lg p-5 mb-4">
-      <h2 class="text-xs text-text-tertiary uppercase tracking-[0.08em] font-medium mb-4">Billing</h2>
-      <div class="flex items-center justify-between">
-        <div>
-          <p class="text-[0.8125rem] text-text-primary">Default Hourly Rate</p>
-          <p class="text-[0.6875rem] text-text-tertiary mt-0.5">Applied to new projects</p>
-        </div>
-        <div class="flex items-center gap-1">
-          <span class="text-[0.8125rem] text-text-tertiary">$</span>
-          <input
-            v-model.number="hourlyRate"
-            type="number"
-            min="0"
-            step="0.01"
-            class="w-24 px-3 py-1.5 bg-bg-inset border border-border-subtle rounded text-[0.8125rem] text-text-primary text-right font-mono focus:outline-none focus:border-border-visible"
-            placeholder="0.00"
-            @change="saveSettings"
-          />
-        </div>
-      </div>
-    </section>
+      <!-- Timer -->
+      <div v-if="activeTab === 'timer'">
+        <h2 class="text-[1.125rem] font-medium text-text-primary mb-6">Timer</h2>
 
-    <!-- 4. Data — export and management -->
-    <section class="bg-bg-surface rounded-lg p-5 mb-4">
-      <h2 class="text-xs text-text-tertiary uppercase tracking-[0.08em] font-medium mb-4">Data</h2>
-      <div class="flex items-center justify-between">
-        <div>
-          <p class="text-[0.8125rem] text-text-primary">Export All Data</p>
-          <p class="text-[0.6875rem] text-text-tertiary mt-0.5">Download as JSON backup</p>
-        </div>
-        <button
-          @click="exportData"
-          class="px-4 py-1.5 border border-border-visible text-text-primary text-[0.8125rem] rounded hover:bg-bg-elevated transition-colors duration-150"
-        >
-          Export
-        </button>
-      </div>
-    </section>
+        <div class="space-y-5">
+          <!-- Idle Detection toggle -->
+          <div class="flex items-center justify-between">
+            <div>
+              <p class="text-[0.8125rem] text-text-primary">Idle Detection</p>
+              <p class="text-[0.6875rem] text-text-tertiary mt-0.5">Detect when you're idle and prompt to continue or stop</p>
+            </div>
+            <button
+              @click="toggleIdleDetection"
+              :class="[
+                'relative inline-flex h-5 w-9 items-center rounded-full transition-colors duration-150',
+                idleDetection ? 'bg-status-running' : 'bg-bg-elevated'
+              ]"
+            >
+              <span
+                :class="[
+                  'inline-block h-3.5 w-3.5 transform rounded-full bg-text-primary transition-transform duration-150',
+                  idleDetection ? 'translate-x-[18px]' : 'translate-x-[3px]'
+                ]"
+              />
+            </button>
+          </div>
 
-    <!-- 5. Danger Zone — destructive actions, isolated at bottom -->
-    <section class="mt-8 rounded-lg border border-status-error/20 p-5">
-      <h2 class="text-xs text-status-error uppercase tracking-[0.08em] font-medium mb-4">Danger Zone</h2>
-      <div class="flex items-center justify-between">
-        <div>
-          <p class="text-[0.8125rem] text-text-primary">Clear All Data</p>
-          <p class="text-[0.6875rem] text-text-tertiary mt-0.5">Permanently delete all entries, projects, clients, and invoices</p>
+          <!-- Reminder Interval — progressive disclosure -->
+          <div
+            v-if="idleDetection"
+            class="flex items-center justify-between pl-4 border-l-2 border-border-subtle ml-1"
+          >
+            <div>
+              <p class="text-[0.8125rem] text-text-primary">Reminder Interval</p>
+              <p class="text-[0.6875rem] text-text-tertiary mt-0.5">Minutes between reminders while running</p>
+            </div>
+            <input
+              v-model.number="reminderInterval"
+              type="number"
+              min="0"
+              max="120"
+              class="w-20 px-3 py-1.5 bg-bg-inset border border-border-subtle rounded text-[0.8125rem] text-text-primary text-right font-mono focus:outline-none focus:border-border-visible"
+              @change="saveSettings"
+            />
+          </div>
         </div>
-        <button
-          @click="showClearDataDialog = true"
-          class="px-4 py-1.5 border border-status-error text-status-error text-[0.8125rem] font-medium rounded hover:bg-status-error/10 transition-colors duration-150"
-        >
-          Clear Data
-        </button>
       </div>
-    </section>
+
+      <!-- Billing -->
+      <div v-if="activeTab === 'billing'">
+        <h2 class="text-[1.125rem] font-medium text-text-primary mb-6">Billing</h2>
+
+        <div class="flex items-center justify-between">
+          <div>
+            <p class="text-[0.8125rem] text-text-primary">Default Hourly Rate</p>
+            <p class="text-[0.6875rem] text-text-tertiary mt-0.5">Applied to new projects</p>
+          </div>
+          <div class="flex items-center gap-1">
+            <span class="text-[0.8125rem] text-text-tertiary">$</span>
+            <input
+              v-model.number="hourlyRate"
+              type="number"
+              min="0"
+              step="0.01"
+              class="w-24 px-3 py-1.5 bg-bg-inset border border-border-subtle rounded text-[0.8125rem] text-text-primary text-right font-mono focus:outline-none focus:border-border-visible"
+              placeholder="0.00"
+              @change="saveSettings"
+            />
+          </div>
+        </div>
+      </div>
+
+      <!-- Data -->
+      <div v-if="activeTab === 'data'">
+        <h2 class="text-[1.125rem] font-medium text-text-primary mb-6">Data</h2>
+
+        <div class="space-y-6">
+          <!-- Export -->
+          <div class="flex items-center justify-between">
+            <div>
+              <p class="text-[0.8125rem] text-text-primary">Export All Data</p>
+              <p class="text-[0.6875rem] text-text-tertiary mt-0.5">Download as JSON backup</p>
+            </div>
+            <button
+              @click="exportData"
+              class="px-4 py-1.5 border border-border-visible text-text-primary text-[0.8125rem] rounded hover:bg-bg-elevated transition-colors duration-150"
+            >
+              Export
+            </button>
+          </div>
+
+          <!-- Danger Zone -->
+          <div class="mt-8 rounded-lg border border-status-error/20 p-5">
+            <h3 class="text-xs text-status-error uppercase tracking-[0.08em] font-medium mb-4">Danger Zone</h3>
+            <div class="flex items-center justify-between">
+              <div>
+                <p class="text-[0.8125rem] text-text-primary">Clear All Data</p>
+                <p class="text-[0.6875rem] text-text-tertiary mt-0.5">Permanently delete all entries, projects, clients, and invoices</p>
+              </div>
+              <button
+                @click="showClearDataDialog = true"
+                class="px-4 py-1.5 border border-status-error text-status-error text-[0.8125rem] font-medium rounded hover:bg-status-error/10 transition-colors duration-150"
+              >
+                Clear Data
+              </button>
+            </div>
+          </div>
+        </div>
+      </div>
+    </div>
 
     <!-- Clear Data Confirmation Dialog -->
     <div
@@ -162,15 +200,25 @@
 </template>
 
 <script setup lang="ts">
-import { ref, onMounted } from 'vue'
+import { ref, onMounted, markRaw } from 'vue'
 import { invoke } from '@tauri-apps/api/core'
-import { Plus, Minus } from 'lucide-vue-next'
+import { Settings as SettingsIcon, Clock, Receipt, Database, Plus, Minus } from 'lucide-vue-next'
 import { useSettingsStore } from '../stores/settings'
 import { useToastStore } from '../stores/toast'
 
 const settingsStore = useSettingsStore()
 const toastStore = useToastStore()
 
+// Tabs
+const tabs = [
+  { id: 'general', label: 'General', icon: markRaw(SettingsIcon) },
+  { id: 'timer', label: 'Timer', icon: markRaw(Clock) },
+  { id: 'billing', label: 'Billing', icon: markRaw(Receipt) },
+  { id: 'data', label: 'Data', icon: markRaw(Database) },
+]
+
+const activeTab = ref('general')
+
 // Settings state
 const hourlyRate = ref(0)
 const idleDetection = ref(true)