diff --git a/static/js/alerts.js b/static/js/alerts.js
new file mode 100644
index 0000000..4336d9d
--- /dev/null
+++ b/static/js/alerts.js
@@ -0,0 +1,11 @@
+document.addEventListener("DOMContentLoaded", () => {
+  document.querySelectorAll("[data-toast-close]").forEach((button) => {
+    button.addEventListener("click", () => {
+      const toast = button.closest(".toast");
+      if (toast) {
+        toast.classList.add("hidden");
+        setTimeout(() => toast.remove(), 200);
+      }
+    });
+  });
+});
diff --git a/static/js/exports.js b/static/js/exports.js
index 5c2a6de..f47e298 100644
--- a/static/js/exports.js
+++ b/static/js/exports.js
@@ -39,20 +39,67 @@ document.addEventListener("DOMContentLoaded", () => {
     const formData = new FormData(form);
     const format = formData.get("format") || "csv";
 
-    const response = await fetch(submitUrl, {
-      method: "POST",
-      headers: {
-        "Content-Type": "application/json",
-      },
-      body: JSON.stringify({
-        format,
-        include_metadata: formData.get("include_metadata") === "true",
-        filters: null,
-      }),
-    });
+    const submitBtn = form.querySelector("button[type='submit']");
+    if (submitBtn) {
+      submitBtn.disabled = true;
+      submitBtn.classList.add("loading");
+    }
+
+    let response;
+    try {
+      response = await fetch(submitUrl, {
+        method: "POST",
+        headers: {
+          "Content-Type": "application/json",
+        },
+        body: JSON.stringify({
+          format,
+          include_metadata: formData.get("include_metadata") === "true",
+          filters: null,
+        }),
+      });
+    } catch (error) {
+      console.error(error);
+      NotificationCenter.show({
+        message: "Network error during export.",
+        level: "error",
+      });
+      const errorContainer = form.querySelector("[data-export-error]");
+      if (errorContainer) {
+        errorContainer.textContent = "Network error during export.";
+        errorContainer.classList.remove("hidden");
+      }
+      submitBtn?.classList.remove("loading");
+      submitBtn?.removeAttribute("disabled");
+      return;
+    }
 
     if (!response.ok) {
-      alert("Export failed. Please try again.");
+      let detail = "Export failed. Please try again.";
+      try {
+        const payload = await response.json();
+        if (payload?.detail) {
+          detail = Array.isArray(payload.detail)
+            ? payload.detail.map((item) => item.msg || item).join("; ")
+            : payload.detail;
+        }
+      } catch (error) {
+        // ignore JSON parse issues
+      }
+
+      NotificationCenter.show({
+        message: detail,
+        level: "error",
+      });
+
+      const errorContainer = form.querySelector("[data-export-error]");
+      if (errorContainer) {
+        errorContainer.textContent = detail;
+        errorContainer.classList.remove("hidden");
+      }
+
+      submitBtn?.classList.remove("loading");
+      submitBtn?.removeAttribute("disabled");
       return;
     }
 
@@ -79,6 +126,14 @@ document.addEventListener("DOMContentLoaded", () => {
     if (modal) {
       closeModal(modal);
     }
+
+    NotificationCenter.show({
+      message: `Export ready: ${filename}`,
+      level: "success",
+    });
+
+    submitBtn?.classList.remove("loading");
+    submitBtn?.removeAttribute("disabled");
   }
 
   document.querySelectorAll("[data-export-trigger]").forEach((button) => {
@@ -90,7 +145,10 @@ document.addEventListener("DOMContentLoaded", () => {
         await loadModal(dataset);
       } catch (error) {
         console.error(error);
-        alert("Unable to open export dialog.");
+        NotificationCenter.show({
+          message: "Unable to open export dialog.",
+          level: "error",
+        });
       }
     });
   });
diff --git a/static/js/imports.js b/static/js/imports.js
index f64480a..c6fff40 100644
--- a/static/js/imports.js
+++ b/static/js/imports.js
@@ -95,6 +95,11 @@ document.addEventListener("DOMContentLoaded", () => {
       uploadButton.classList.add("loading");
 
       // Actual upload logic handled separately (e.g., fetch).
+      NotificationCenter?.show({
+        message: "Upload started…",
+        level: "info",
+        timeout: 2000,
+      });
     });
   });
 });
diff --git a/static/js/notifications.js b/static/js/notifications.js
new file mode 100644
index 0000000..8842ba5
--- /dev/null
+++ b/static/js/notifications.js
@@ -0,0 +1,38 @@
+(() => {
+  let container;
+
+  function ensureContainer() {
+    if (!container) {
+      container = document.createElement("div");
+      container.className = "toast-container";
+      document.body.appendChild(container);
+    }
+    return container;
+  }
+
+  function show({ message, level = "info", timeout = 5000 } = {}) {
+    const root = ensureContainer();
+    const toast = document.createElement("div");
+    toast.className = `toast toast--${level}`;
+    toast.setAttribute("role", "alert");
+    toast.innerHTML = `
+      <span class="toast__icon" aria-hidden="true"></span>
+      <p class="toast__message">${message}</p>
+      <button type="button" class="toast__close" aria-label="Dismiss">×</button>
+    `;
+    root.appendChild(toast);
+
+    const close = () => {
+      toast.classList.add("hidden");
+      setTimeout(() => toast.remove(), 200);
+    };
+
+    toast.querySelector(".toast__close").addEventListener("click", close);
+
+    if (timeout > 0) {
+      setTimeout(close, timeout);
+    }
+  }
+
+  window.NotificationCenter = { show };
+})();
diff --git a/templates/base.html b/templates/base.html
index a7c9700..2169b4d 100644
--- a/templates/base.html
+++ b/templates/base.html
@@ -24,6 +24,7 @@
   <script src="/static/js/projects.js" defer></script>
   <script src="/static/js/exports.js" defer></script>
   <script src="/static/js/imports.js" defer></script>
+  <script src="/static/js/notifications.js" defer></script>
     <script src="/static/js/theme.js"></script>
   </body>
 </html>
diff --git a/templates/exports/modal.html b/templates/exports/modal.html
index 6da58db..7f1a107 100644
--- a/templates/exports/modal.html
+++ b/templates/exports/modal.html
@@ -45,6 +45,7 @@
           </button>
           <button type="submit" class="btn btn-primary">Download</button>
         </div>
+        <p class="form-error hidden" data-export-error></p>
       </form>
     </div>
   </div>