diff --git a/src/lib/stores/profiles.svelte.ts b/src/lib/stores/profiles.svelte.ts
new file mode 100644
index 0000000..a913be7
--- /dev/null
+++ b/src/lib/stores/profiles.svelte.ts
@@ -0,0 +1,123 @@
+import { invoke } from "@tauri-apps/api/core";
+
+import { toasts } from "$lib/stores/toasts.svelte.ts";
+import { errorMessage } from "$lib/utils/errors.js";
+import { hasTauriRuntime } from "$lib/utils/runtime.js";
+
+// Matches the SQLite-seeded Default profile UUID (see migration v6). Used as
+// the in-memory default for `activeProfileId` on boot. Cross-session
+// persistence of the selection is out of scope for Phase 2 — see Task 14
+// plan notes.
+export const DEFAULT_PROFILE_ID = "00000000-0000-0000-0000-000000000001";
+
+// DTOs mirror the serde-camelCase shape emitted by the Tauri commands added
+// in Task 12. Kept local to this store until a second consumer appears.
+export interface ProfileDto {
+  id: string;
+  name: string;
+  initialPrompt: string;
+  createdAt: string;
+}
+
+export interface ProfileTermDto {
+  id: string;
+  profileId: string;
+  term: string;
+  note: string;
+  createdAt: string;
+}
+
+let profilesState = $state<ProfileDto[]>([]);
+let activeProfileIdState = $state<string>(DEFAULT_PROFILE_ID);
+
+export const profilesStore = {
+  get profiles(): ProfileDto[] {
+    return profilesState;
+  },
+  get activeProfileId(): string {
+    return activeProfileIdState;
+  },
+  get active(): ProfileDto | null {
+    return profilesState.find((p) => p.id === activeProfileIdState) ?? null;
+  },
+
+  async load(): Promise<void> {
+    if (!hasTauriRuntime()) return;
+    try {
+      profilesState = await invoke<ProfileDto[]>("list_profiles_cmd");
+    } catch (err) {
+      toasts.error("Failed to load profiles", errorMessage(err));
+    }
+  },
+
+  setActive(id: string): void {
+    if (profilesState.find((p) => p.id === id)) {
+      activeProfileIdState = id;
+    }
+  },
+
+  async create(name: string, initialPrompt: string): Promise<ProfileDto | null> {
+    if (!hasTauriRuntime()) return null;
+    try {
+      const row = await invoke<ProfileDto>("create_profile_cmd", {
+        name,
+        initialPrompt,
+      });
+      profilesState = [...profilesState, row];
+      return row;
+    } catch (err) {
+      toasts.error("Failed to create profile", errorMessage(err));
+      return null;
+    }
+  },
+
+  async update(id: string, name: string, initialPrompt: string): Promise<void> {
+    if (!hasTauriRuntime()) return;
+    try {
+      await invoke("update_profile_cmd", { id, name, initialPrompt });
+      profilesState = profilesState.map((p) =>
+        p.id === id ? { ...p, name, initialPrompt } : p,
+      );
+    } catch (err) {
+      toasts.error("Failed to update profile", errorMessage(err));
+    }
+  },
+
+  async delete(id: string): Promise<void> {
+    if (id === DEFAULT_PROFILE_ID) {
+      toasts.error("Default profile cannot be deleted");
+      return;
+    }
+    if (!hasTauriRuntime()) return;
+    try {
+      await invoke("delete_profile_cmd", { id });
+      profilesState = profilesState.filter((p) => p.id !== id);
+      if (activeProfileIdState === id) activeProfileIdState = DEFAULT_PROFILE_ID;
+    } catch (err) {
+      toasts.error("Failed to delete profile", errorMessage(err));
+    }
+  },
+
+  async listTerms(profileId: string): Promise<ProfileTermDto[]> {
+    if (!hasTauriRuntime()) return [];
+    return invoke<ProfileTermDto[]>("list_profile_terms_cmd", { profileId });
+  },
+
+  async addTerm(
+    profileId: string,
+    term: string,
+    note = "",
+  ): Promise<ProfileTermDto | null> {
+    if (!hasTauriRuntime()) return null;
+    return invoke<ProfileTermDto>("add_profile_term_cmd", {
+      profileId,
+      term,
+      note,
+    });
+  },
+
+  async deleteTerm(termId: string): Promise<void> {
+    if (!hasTauriRuntime()) return;
+    await invoke("delete_profile_term_cmd", { id: termId });
+  },
+};