diff --git a/packages/app-elements/src/ui/composite/Modal.test.tsx b/packages/app-elements/src/ui/composite/Modal.test.tsx
new file mode 100644
index 000000000..9f331fdb4
--- /dev/null
+++ b/packages/app-elements/src/ui/composite/Modal.test.tsx
@@ -0,0 +1,218 @@
+import { fireEvent, render } from "@testing-library/react"
+import { Modal } from "./Modal"
+
+interface SetupOptions {
+  dismissible?: boolean
+  show?: boolean
+}
+
+const setup = ({ dismissible = false, show = true }: SetupOptions = {}) => {
+  const onClose = vi.fn()
+
+  const utils = render(
+    <Modal show={show} onClose={onClose} dismissible={dismissible}>
+      <Modal.Header>My Modal</Modal.Header>
+      <Modal.Body>Body</Modal.Body>
+    </Modal>,
+  )
+
+  const dialog = document.body.querySelector("dialog") as HTMLDialogElement
+  const backdrop = utils.getByTestId("modal-backdrop")
+  const closeButton = utils.getByLabelText("Close")
+
+  return {
+    ...utils,
+    onClose,
+    dialog,
+    backdrop,
+    closeButton,
+  }
+}
+
+describe("Modal", () => {
+  test("Should not close on backdrop click when dismissible is false", () => {
+    const { backdrop, onClose } = setup({ dismissible: false })
+
+    fireEvent.click(backdrop)
+
+    expect(onClose).not.toHaveBeenCalled()
+  })
+
+  test("Should not close on Escape cancel event when dismissible is false", () => {
+    const { dialog, onClose } = setup({ dismissible: false })
+
+    fireEvent(dialog, new Event("cancel", { cancelable: true }))
+
+    expect(onClose).not.toHaveBeenCalled()
+  })
+
+  test("Should not close from keyboard activation on close button when dismissible is false", () => {
+    const { closeButton, onClose } = setup({ dismissible: false })
+
+    fireEvent.keyDown(closeButton, { key: "Enter" })
+    fireEvent.keyDown(closeButton, { key: " " })
+
+    expect(onClose).not.toHaveBeenCalled()
+  })
+
+  test("Should close on close button click when dismissible is false", () => {
+    const { closeButton, onClose } = setup({ dismissible: false })
+
+    fireEvent.click(closeButton)
+
+    expect(onClose).toHaveBeenCalledTimes(1)
+  })
+
+  test("Should close on backdrop click when dismissible is true", () => {
+    const { backdrop, onClose } = setup({ dismissible: true })
+
+    fireEvent.click(backdrop)
+
+    expect(onClose).toHaveBeenCalledTimes(1)
+  })
+
+  test("Should close on Escape cancel event when dismissible is true", () => {
+    const { dialog, onClose } = setup({ dismissible: true })
+
+    fireEvent(dialog, new Event("cancel", { cancelable: true }))
+
+    expect(onClose).toHaveBeenCalledTimes(1)
+  })
+
+  test("Should keep dialog visibility in sync across open-close-open cycle", () => {
+    const onClose = vi.fn()
+    const { rerender } = render(
+      <Modal show={false} onClose={onClose} dismissible>
+        <Modal.Header>My Modal</Modal.Header>
+        <Modal.Body>Body</Modal.Body>
+      </Modal>,
+    )
+
+    const dialog = document.body.querySelector("dialog") as HTMLDialogElement
+    expect(dialog).toHaveClass("hidden")
+    expect(dialog.open).toBe(false)
+
+    rerender(
+      <Modal show onClose={onClose} dismissible>
+        <Modal.Header>My Modal</Modal.Header>
+        <Modal.Body>Body</Modal.Body>
+      </Modal>,
+    )
+    expect(dialog).toHaveClass("grid")
+    expect(dialog.open).toBe(true)
+
+    rerender(
+      <Modal show={false} onClose={onClose} dismissible>
+        <Modal.Header>My Modal</Modal.Header>
+        <Modal.Body>Body</Modal.Body>
+      </Modal>,
+    )
+    expect(dialog).toHaveClass("hidden")
+    expect(dialog.open).toBe(false)
+
+    rerender(
+      <Modal show onClose={onClose} dismissible>
+        <Modal.Header>My Modal</Modal.Header>
+        <Modal.Body>Body</Modal.Body>
+      </Modal>,
+    )
+    expect(dialog).toHaveClass("grid")
+    expect(dialog.open).toBe(true)
+  })
+
+  test("Should use ariaLabel when Modal.Header is not rendered", () => {
+    const onClose = vi.fn()
+    render(
+      <Modal show onClose={onClose} ariaLabel="Details panel" dismissible>
+        <Modal.Body>Body</Modal.Body>
+      </Modal>,
+    )
+
+    expect(document.body.querySelector("dialog")).toHaveAttribute(
+      "aria-label",
+      "Details panel",
+    )
+  })
+
+  test("Should keep backdrop out of tab order", () => {
+    const { backdrop } = setup({ dismissible: true })
+
+    expect(backdrop).toHaveAttribute("tabindex", "-1")
+  })
+
+  test("Should keep aria-labelledby associations unique with multiple modals", () => {
+    const onClose = vi.fn()
+    render(
+      <>
+        <Modal show onClose={onClose} dismissible>
+          <Modal.Header>First Modal</Modal.Header>
+          <Modal.Body>Body</Modal.Body>
+        </Modal>
+        <Modal show onClose={onClose} dismissible>
+          <Modal.Header>Second Modal</Modal.Header>
+          <Modal.Body>Body</Modal.Body>
+        </Modal>
+      </>,
+    )
+
+    const dialogs = Array.from(document.body.querySelectorAll("dialog"))
+    expect(dialogs).toHaveLength(2)
+
+    const firstLabelId = dialogs[0]?.getAttribute("aria-labelledby")
+    const secondLabelId = dialogs[1]?.getAttribute("aria-labelledby")
+
+    expect(firstLabelId).toBeTruthy()
+    expect(secondLabelId).toBeTruthy()
+    expect(firstLabelId).not.toBe(secondLabelId)
+    expect(document.getElementById(firstLabelId ?? "")).toBeInTheDocument()
+    expect(document.getElementById(secondLabelId ?? "")).toBeInTheDocument()
+  })
+
+  test("Should fallback to open property when showModal/close are unavailable", () => {
+    const onClose = vi.fn()
+    const { rerender } = render(
+      <Modal show={false} onClose={onClose} dismissible>
+        <Modal.Header>My Modal</Modal.Header>
+        <Modal.Body>Body</Modal.Body>
+      </Modal>,
+    )
+
+    const dialog = document.body.querySelector("dialog") as HTMLDialogElement
+    const originalShowModal = dialog.showModal
+    const originalClose = dialog.close
+
+    Object.defineProperty(dialog, "showModal", {
+      configurable: true,
+      value: undefined,
+    })
+    Object.defineProperty(dialog, "close", {
+      configurable: true,
+      value: undefined,
+    })
+
+    rerender(
+      <Modal show onClose={onClose} dismissible>
+        <Modal.Header>My Modal</Modal.Header>
+        <Modal.Body>Body</Modal.Body>
+      </Modal>,
+    )
+    expect(dialog.open).toBe(true)
+
+    rerender(
+      <Modal show={false} onClose={onClose} dismissible>
+        <Modal.Header>My Modal</Modal.Header>
+        <Modal.Body>Body</Modal.Body>
+      </Modal>,
+    )
+    expect(dialog.open).toBe(false)
+
+    Object.defineProperty(dialog, "showModal", {
+      configurable: true,
+      value: originalShowModal,
+    })
+    Object.defineProperty(dialog, "close", {
+      configurable: true,
+      value: originalClose,
+    })
+  })
+})
diff --git a/packages/app-elements/src/ui/composite/Modal.tsx b/packages/app-elements/src/ui/composite/Modal.tsx
index 8247d45f7..9e500d4a3 100644
--- a/packages/app-elements/src/ui/composite/Modal.tsx
+++ b/packages/app-elements/src/ui/composite/Modal.tsx
@@ -1,6 +1,13 @@
 import cn from "classnames"
 import type React from "react"
-import { createContext, useContext, useEffect, useId } from "react"
+import {
+  createContext,
+  forwardRef,
+  useContext,
+  useEffect,
+  useId,
+  useRef,
+} from "react"
 import { createPortal } from "react-dom"
 import { Icon } from "#ui/atoms/Icon"
 
@@ -8,6 +15,7 @@ import { Icon } from "#ui/atoms/Icon"
 const ModalContext = createContext<{
   onClose: () => void
   modalId: string
+  dismissible: boolean
 } | null>(null)
 
 // Hook to use modal context
@@ -22,97 +30,140 @@ const useModalContext = () => {
 export type ModalProps = {
   /** Whether the modal is open */
   show?: boolean
-  /** Called when user clicks backdrop or the close button */
+  /** Accessible name fallback used when Modal.Header is not rendered. */
+  ariaLabel?: string
+  /** Called when the modal requests to close (e.g. header close button, and backdrop/Escape when `dismissible` is true). */
   onClose: () => void
   /** Modal content */
   children: React.ReactNode
   /** Max width preset */
   size?: "large" | "small" | "x-small"
+  /**
+   * Enables modal dismissal via backdrop click and Escape key.
+   *
+   * - true: backdrop + Escape can trigger onClose.
+   * - false: backdrop + Escape are ignored; closing is allowed only via mouse click on the header close button.
+   *
+   * Note: when false, keyboard activation (Enter/Space) on the close button is intentionally blocked.
+   */
+  dismissible?: boolean
 }
 
-export const Modal: React.FC<
-  ModalProps & { ref?: React.RefObject<HTMLDivElement | null> }
+type ModalComponent = React.ForwardRefExoticComponent<
+  ModalProps & React.RefAttributes<HTMLDivElement>
 > & {
   Header: React.FC<React.PropsWithChildren>
   Body: React.FC<React.PropsWithChildren>
   Footer: React.FC<React.PropsWithChildren>
-} = ({ ref, show = false, children, onClose, size = "small" }) => {
+}
+
+const ModalRoot = (
+  {
+    show = false,
+    ariaLabel,
+    children,
+    onClose,
+    size = "small",
+    dismissible = false,
+  }: ModalProps,
+  ref: React.ForwardedRef<HTMLDivElement>,
+) => {
   const modalId = useId()
+  const dialogRef = useRef<HTMLDialogElement | null>(null)
 
   useEffect(
-    function preventBodyScrollbar() {
-      if (show) {
-        document.body.classList.add("overflow-hidden")
+    function syncDialogVisibility() {
+      const dialog = dialogRef.current
+      if (!dialog) return
+
+      if (show && !dialog.open) {
+        if (typeof dialog.showModal === "function") {
+          dialog.showModal()
+        } else {
+          dialog.open = true
+        }
+        return
       }
 
-      return () => {
-        document.body.classList.remove("overflow-hidden")
+      if (!show && dialog.open) {
+        if (typeof dialog.close === "function") {
+          dialog.close()
+        } else {
+          dialog.open = false
+        }
       }
     },
     [show],
   )
 
   const content = (
-    <ModalContext.Provider value={{ onClose, modalId }}>
+    <ModalContext.Provider value={{ onClose, modalId, dismissible }}>
       <div
         className={cn(
           "bg-white rounded-md shadow-xl",
           "max-h-[90vh] flex flex-col",
         )}
-        role="dialog"
-        aria-modal="true"
-        aria-labelledby={`${modalId}-title`}
-        onClick={(e) => {
-          e.stopPropagation()
-        }}
-        onKeyDown={(e) => {
-          // stop closing when pressing keys inside the dialog
-          if (e.key === "Escape" || e.key === "Enter" || e.key === " ") {
-            e.stopPropagation()
-          }
-        }}
       >
         {children}
       </div>
     </ModalContext.Provider>
   )
 
+  /**
+   * The modal is rendered in a portal and uses the native dialog element for
+   * keyboard and focus behavior. Backdrop click/Escape can request close unless
+   * `dismissible` is false.
+   */
   return createPortal(
     <div ref={ref}>
-      {show && (
-        <>
-          <button
-            disabled={true}
-            type="button"
-            aria-label="Close modal"
-            className="fixed inset-0 z-60 bg-gray-900/90 animate-backdrop-fade-in cursor-default"
-            onClick={onClose}
-            onKeyDown={(e) => {
-              if (e.key === "Escape" || e.key === "Enter" || e.key === " ") {
-                onClose()
-              }
-            }}
-          />
-          <div
-            className={cn(
-              "fixed z-70 w-full top-1/2 left-1/2 -translate-x-1/2 -translate-y-1/2",
-              size === "large" && "max-w-155 md:w-155",
-              size === "small" && "max-w-105 md:w-105",
-              size === "x-small" && "max-w-80 md:w-80",
-            )}
-            data-testid="modal"
-          >
-            {content}
-          </div>
-        </>
-      )}
+      <dialog
+        ref={dialogRef}
+        aria-labelledby={ariaLabel != null ? undefined : `${modalId}-title`}
+        aria-label={ariaLabel}
+        className={cn(
+          "fixed inset-0 m-0 p-4 border-none bg-transparent w-screen h-screen max-w-none max-h-none overflow-visible place-items-center backdrop:bg-transparent",
+          show ? "grid" : "hidden",
+        )}
+        onCancel={(event) => {
+          event.preventDefault()
+          if (dismissible) {
+            onClose()
+          }
+        }}
+      >
+        <button
+          type="button"
+          tabIndex={-1}
+          disabled={!dismissible}
+          aria-hidden={!dismissible}
+          aria-label="Dismiss modal backdrop"
+          data-testid="modal-backdrop"
+          className="fixed inset-0 z-60 bg-gray-900/90 animate-backdrop-fade-in"
+          onClick={onClose}
+        />
+        <div
+          className={cn(
+            "relative z-70 w-full",
+            size === "large" && "max-w-155 md:w-155",
+            size === "small" && "max-w-105 md:w-105",
+            size === "x-small" && "max-w-80 md:w-80",
+          )}
+          data-testid="modal"
+        >
+          {content}
+        </div>
+      </dialog>
     </div>,
     document.body,
   )
 }
 
+export const Modal = forwardRef<HTMLDivElement, ModalProps>(
+  ModalRoot,
+) as ModalComponent
+
 Modal.Header = ({ children }) => {
-  const { onClose, modalId } = useModalContext()
+  const { onClose, modalId, dismissible } = useModalContext()
 
   return (
     <div className="flex-none flex items-center justify-between px-6 py-4 border-b border-gray-200">
@@ -124,6 +175,13 @@ Modal.Header = ({ children }) => {
         aria-label="Close"
         className="p-2 -m-2"
         onClick={onClose}
+        onKeyDown={(event) => {
+          // Product requirement: when dismissible=false, modal must close only on mouse click.
+          // Block keyboard activation on the close button (Enter/Space).
+          if (!dismissible && (event.key === "Enter" || event.key === " ")) {
+            event.preventDefault()
+          }
+        }}
       >
         <Icon name="x" size={16} />
       </button>
diff --git a/packages/docs/src/stories/composite/Modal.stories.tsx b/packages/docs/src/stories/composite/Modal.stories.tsx
index b6a467873..ddeb9f8ed 100644
--- a/packages/docs/src/stories/composite/Modal.stories.tsx
+++ b/packages/docs/src/stories/composite/Modal.stories.tsx
@@ -70,6 +70,28 @@ export const Default: StoryFn = () => {
   )
 }
 
+/**
+ * Modal that can be dismissed by clicking the backdrop or pressing Esc.
+ */
+export const Dismissible: StoryFn = () => {
+  const [show, setShow] = useState(false)
+
+  const handleClose = () => setShow(false)
+  const handleShow = () => setShow(true)
+
+  return (
+    <div>
+      <Button onClick={handleShow}>Open dismissible modal</Button>
+      <Modal show={show} onClose={handleClose} dismissible>
+        <Modal.Header>Dismissible modal</Modal.Header>
+        <Modal.Body>
+          This modal can be closed by clicking outside or pressing Escape.
+        </Modal.Body>
+      </Modal>
+    </div>
+  )
+}
+
 /**
  * Modal with a long, scrollable content.
  */