diff --git a/packages/core/src/components/dialog/dialog-close.tsx b/packages/core/src/components/dialog/dialog-close.tsx
new file mode 100644
index 0000000..9a3fd10
--- /dev/null
+++ b/packages/core/src/components/dialog/dialog-close.tsx
@@ -0,0 +1,28 @@
+// packages/core/src/components/dialog/dialog-close.tsx
+import type { Component, JSX } from "solid-js";
+import { splitProps } from "solid-js";
+import { Dynamic } from "solid-js/web";
+import { useInternalDialogContext } from "./dialog-context";
+
+export interface DialogCloseProps extends JSX.HTMLAttributes<HTMLButtonElement> {
+  as?: string | Component;
+  children?: JSX.Element;
+}
+
+/** Closes the dialog when clicked. Supports polymorphic rendering via `as`. */
+export function DialogClose(props: DialogCloseProps): JSX.Element {
+  const [local, rest] = splitProps(props, ["as", "children", "onClick"]);
+  const ctx = useInternalDialogContext();
+
+  const handleClick: JSX.EventHandler<HTMLElement, MouseEvent> = (e) => {
+    if (typeof local.onClick === "function")
+      local.onClick(e as MouseEvent & { currentTarget: HTMLButtonElement; target: Element });
+    ctx.setOpen(false);
+  };
+
+  return (
+    <Dynamic component={local.as ?? "button"} onClick={handleClick} {...rest}>
+      {local.children}
+    </Dynamic>
+  );
+}
diff --git a/packages/core/src/components/dialog/dialog-content.tsx b/packages/core/src/components/dialog/dialog-content.tsx
new file mode 100644
index 0000000..8767854
--- /dev/null
+++ b/packages/core/src/components/dialog/dialog-content.tsx
@@ -0,0 +1,76 @@
+// packages/core/src/components/dialog/dialog-content.tsx
+import type { JSX } from "solid-js";
+import { Show, onCleanup, onMount, splitProps } from "solid-js";
+import { createDismiss } from "../../utilities/dismiss/create-dismiss";
+import { createFocusTrap } from "../../utilities/focus-trap/create-focus-trap";
+import { Portal } from "../../utilities/portal/portal";
+import { createScrollLock } from "../../utilities/scroll-lock/create-scroll-lock";
+import { useInternalDialogContext } from "./dialog-context";
+
+export interface DialogContentProps extends JSX.DialogHtmlAttributes<HTMLDialogElement> {
+  /**
+   * Called when auto-focus fires on open. Call event.preventDefault() to prevent default.
+   */
+  onOpenAutoFocus?: (event: Event) => void;
+  /**
+   * Called when auto-focus fires on close. Call event.preventDefault() to prevent default.
+   */
+  onCloseAutoFocus?: (event: Event) => void;
+  /** Keep mounted even when closed (for animation control). */
+  forceMount?: boolean;
+  children?: JSX.Element;
+}
+
+/**
+ * Dialog content panel. Portals to body, manages focus trap, scroll lock, and dismiss.
+ * Only renders when open (unless forceMount is set).
+ */
+export function DialogContent(props: DialogContentProps): JSX.Element {
+  const [local, rest] = splitProps(props, [
+    "children",
+    "onOpenAutoFocus",
+    "onCloseAutoFocus",
+    "forceMount",
+  ]);
+  const ctx = useInternalDialogContext();
+  let contentRef: HTMLDialogElement | undefined;
+
+  const focusTrap = createFocusTrap(() => contentRef ?? null);
+  const scrollLock = createScrollLock();
+  const dismiss = createDismiss({
+    getContainer: () => contentRef ?? null,
+    onDismiss: () => ctx.setOpen(false),
+  });
+
+  onMount(() => {
+    if (ctx.isOpen() && ctx.modal()) {
+      focusTrap.activate();
+      scrollLock.lock();
+      dismiss.attach();
+    }
+  });
+
+  onCleanup(() => {
+    focusTrap.deactivate();
+    scrollLock.unlock();
+    dismiss.detach();
+  });
+
+  return (
+    <Show when={local.forceMount || ctx.isOpen()}>
+      <Portal>
+        <dialog
+          ref={contentRef}
+          id={ctx.contentId()}
+          aria-modal={ctx.modal() || undefined}
+          aria-labelledby={ctx.titleId()}
+          aria-describedby={ctx.descriptionId()}
+          data-state={ctx.isOpen() ? "open" : "closed"}
+          {...rest}
+        >
+          {local.children}
+        </dialog>
+      </Portal>
+    </Show>
+  );
+}
diff --git a/packages/core/src/components/dialog/dialog-description.tsx b/packages/core/src/components/dialog/dialog-description.tsx
new file mode 100644
index 0000000..06eab78
--- /dev/null
+++ b/packages/core/src/components/dialog/dialog-description.tsx
@@ -0,0 +1,24 @@
+// packages/core/src/components/dialog/dialog-description.tsx
+import type { JSX } from "solid-js";
+import { createUniqueId, onCleanup, onMount, splitProps } from "solid-js";
+import { useInternalDialogContext } from "./dialog-context";
+
+export interface DialogDescriptionProps extends JSX.HTMLAttributes<HTMLParagraphElement> {
+  children?: JSX.Element;
+}
+
+/** Renders as p and registers its ID for aria-describedby on Dialog.Content. */
+export function DialogDescription(props: DialogDescriptionProps): JSX.Element {
+  const [local, rest] = splitProps(props, ["children"]);
+  const ctx = useInternalDialogContext();
+  const id = createUniqueId();
+
+  onMount(() => ctx.setDescriptionId(id));
+  onCleanup(() => ctx.setDescriptionId(undefined));
+
+  return (
+    <p id={id} {...rest}>
+      {local.children}
+    </p>
+  );
+}
diff --git a/packages/core/src/components/dialog/dialog-overlay.tsx b/packages/core/src/components/dialog/dialog-overlay.tsx
new file mode 100644
index 0000000..2fcc991
--- /dev/null
+++ b/packages/core/src/components/dialog/dialog-overlay.tsx
@@ -0,0 +1,20 @@
+// packages/core/src/components/dialog/dialog-overlay.tsx
+import type { JSX } from "solid-js";
+import { Show, splitProps } from "solid-js";
+import { useInternalDialogContext } from "./dialog-context";
+
+export interface DialogOverlayProps extends JSX.HTMLAttributes<HTMLDivElement> {
+  forceMount?: boolean;
+}
+
+/** Semi-transparent overlay rendered behind dialog content. */
+export function DialogOverlay(props: DialogOverlayProps): JSX.Element {
+  const [local, rest] = splitProps(props, ["forceMount"]);
+  const ctx = useInternalDialogContext();
+
+  return (
+    <Show when={local.forceMount || ctx.isOpen()}>
+      <div aria-hidden="true" data-state={ctx.isOpen() ? "open" : "closed"} {...rest} />
+    </Show>
+  );
+}
diff --git a/packages/core/src/components/dialog/dialog-portal.tsx b/packages/core/src/components/dialog/dialog-portal.tsx
new file mode 100644
index 0000000..8893cb4
--- /dev/null
+++ b/packages/core/src/components/dialog/dialog-portal.tsx
@@ -0,0 +1,20 @@
+// packages/core/src/components/dialog/dialog-portal.tsx
+import type { JSX } from "solid-js";
+import { splitProps } from "solid-js";
+import { Portal } from "../../utilities/portal/portal";
+
+export interface DialogPortalProps {
+  /** Override the portal target container. */
+  target?: Element | null;
+  children: JSX.Element;
+}
+
+/** Renders children into a portal (defaults to document.body). */
+export function DialogPortal(props: DialogPortalProps): JSX.Element {
+  const [local, rest] = splitProps(props, ["target", "children"]);
+  return local.target !== undefined ? (
+    <Portal target={local.target}>{local.children}</Portal>
+  ) : (
+    <Portal>{local.children}</Portal>
+  );
+}
diff --git a/packages/core/src/components/dialog/dialog-root.tsx b/packages/core/src/components/dialog/dialog-root.tsx
new file mode 100644
index 0000000..13d132f
--- /dev/null
+++ b/packages/core/src/components/dialog/dialog-root.tsx
@@ -0,0 +1,72 @@
+// packages/core/src/components/dialog/dialog-root.tsx
+import type { JSX } from "solid-js";
+import { createSignal } from "solid-js";
+import {
+  type CreateDisclosureStateOptions,
+  createDisclosureState,
+} from "../../primitives/create-disclosure-state";
+import { createRegisterId } from "../../primitives/create-register-id";
+import {
+  DialogContextProvider,
+  InternalDialogContextProvider,
+  type InternalDialogContextValue,
+} from "./dialog-context";
+
+export interface DialogRootProps {
+  /** Controlled open state. */
+  open?: boolean;
+  /** Default open state (uncontrolled). */
+  defaultOpen?: boolean;
+  /** Called when open state should change. */
+  onOpenChange?: (open: boolean) => void;
+  /**
+   * Whether the dialog blocks outside interaction and traps focus.
+   * @default true
+   */
+  modal?: boolean;
+  children: JSX.Element;
+}
+
+/**
+ * Root component. Manages open state, provides context to all Dialog parts.
+ * Renders no DOM elements itself.
+ */
+export function DialogRoot(props: DialogRootProps): JSX.Element {
+  const disclosure = createDisclosureState({
+    get open() {
+      return props.open;
+    },
+    get defaultOpen() {
+      return props.defaultOpen;
+    },
+    get onOpenChange() {
+      return props.onOpenChange;
+    },
+  } as CreateDisclosureStateOptions);
+
+  const contentId = `pettyui-dialog-${Math.random().toString(36).slice(2, 9)}`;
+  const [titleId, setTitleId] = createRegisterId();
+  const [descriptionId, setDescriptionId] = createRegisterId();
+  const [hasTrigger, setHasTrigger] = createSignal(false);
+
+  const internalCtx: InternalDialogContextValue = {
+    isOpen: disclosure.isOpen,
+    setOpen: (open) => (open ? disclosure.open() : disclosure.close()),
+    modal: () => props.modal ?? true,
+    contentId: () => contentId,
+    titleId,
+    setTitleId,
+    descriptionId,
+    setDescriptionId,
+    hasTrigger,
+    setHasTrigger,
+  };
+
+  return (
+    <InternalDialogContextProvider value={internalCtx}>
+      <DialogContextProvider value={{ open: disclosure.isOpen, modal: () => props.modal ?? true }}>
+        {props.children}
+      </DialogContextProvider>
+    </InternalDialogContextProvider>
+  );
+}
diff --git a/packages/core/src/components/dialog/dialog-title.tsx b/packages/core/src/components/dialog/dialog-title.tsx
new file mode 100644
index 0000000..4eeafa3
--- /dev/null
+++ b/packages/core/src/components/dialog/dialog-title.tsx
@@ -0,0 +1,24 @@
+// packages/core/src/components/dialog/dialog-title.tsx
+import type { JSX } from "solid-js";
+import { createUniqueId, onCleanup, onMount, splitProps } from "solid-js";
+import { useInternalDialogContext } from "./dialog-context";
+
+export interface DialogTitleProps extends JSX.HTMLAttributes<HTMLHeadingElement> {
+  children?: JSX.Element;
+}
+
+/** Renders as h2 and registers its ID for aria-labelledby on Dialog.Content. */
+export function DialogTitle(props: DialogTitleProps): JSX.Element {
+  const [local, rest] = splitProps(props, ["children"]);
+  const ctx = useInternalDialogContext();
+  const id = createUniqueId();
+
+  onMount(() => ctx.setTitleId(id));
+  onCleanup(() => ctx.setTitleId(undefined));
+
+  return (
+    <h2 id={id} {...rest}>
+      {local.children}
+    </h2>
+  );
+}
diff --git a/packages/core/src/components/dialog/dialog-trigger.tsx b/packages/core/src/components/dialog/dialog-trigger.tsx
new file mode 100644
index 0000000..24e6e22
--- /dev/null
+++ b/packages/core/src/components/dialog/dialog-trigger.tsx
@@ -0,0 +1,42 @@
+// packages/core/src/components/dialog/dialog-trigger.tsx
+import type { Component, JSX } from "solid-js";
+import { mergeProps, splitProps } from "solid-js";
+import { Dynamic } from "solid-js/web";
+import { useInternalDialogContext } from "./dialog-context";
+
+export interface DialogTriggerProps
+  extends Omit<JSX.HTMLAttributes<HTMLButtonElement>, "children"> {
+  /** Render as a different element or component. */
+  as?: string | Component;
+  children?: JSX.Element | ((props: JSX.HTMLAttributes<HTMLElement>) => JSX.Element);
+}
+
+/** Opens the dialog when clicked. Supports polymorphic rendering via `as` and children-as-function. */
+export function DialogTrigger(props: DialogTriggerProps): JSX.Element {
+  const [local, rest] = splitProps(props, ["as", "children", "onClick"]);
+  const ctx = useInternalDialogContext();
+
+  const handleClick: JSX.EventHandler<HTMLElement, MouseEvent> = (e) => {
+    if (typeof local.onClick === "function")
+      local.onClick(e as MouseEvent & { currentTarget: HTMLButtonElement; target: Element });
+    ctx.setOpen(!ctx.isOpen());
+  };
+
+  const triggerProps = mergeProps(rest, {
+    "aria-haspopup": "dialog" as const,
+    "aria-expanded": ctx.isOpen(),
+    "aria-controls": ctx.contentId(),
+    "data-state": ctx.isOpen() ? "open" : "closed",
+    onClick: handleClick,
+  });
+
+  if (typeof local.children === "function") {
+    return <>{local.children(triggerProps as JSX.HTMLAttributes<HTMLElement>)}</>;
+  }
+
+  return (
+    <Dynamic component={local.as ?? "button"} {...triggerProps}>
+      {local.children}
+    </Dynamic>
+  );
+}
diff --git a/packages/core/src/components/dialog/index.ts b/packages/core/src/components/dialog/index.ts
new file mode 100644
index 0000000..4697ea8
--- /dev/null
+++ b/packages/core/src/components/dialog/index.ts
@@ -0,0 +1,30 @@
+import { DialogClose } from "./dialog-close";
+import { DialogContent } from "./dialog-content";
+import { useDialogContext } from "./dialog-context";
+import { DialogDescription } from "./dialog-description";
+import { DialogOverlay } from "./dialog-overlay";
+import { DialogPortal } from "./dialog-portal";
+// packages/core/src/components/dialog/index.ts
+import { DialogRoot } from "./dialog-root";
+import { DialogTitle } from "./dialog-title";
+import { DialogTrigger } from "./dialog-trigger";
+
+export const Dialog = Object.assign(DialogRoot, {
+  Content: DialogContent,
+  Title: DialogTitle,
+  Description: DialogDescription,
+  Trigger: DialogTrigger,
+  Close: DialogClose,
+  Portal: DialogPortal,
+  Overlay: DialogOverlay,
+  useContext: useDialogContext,
+});
+
+export type { DialogRootProps } from "./dialog-root";
+export type { DialogContentProps } from "./dialog-content";
+export type { DialogTitleProps } from "./dialog-title";
+export type { DialogDescriptionProps } from "./dialog-description";
+export type { DialogTriggerProps } from "./dialog-trigger";
+export type { DialogCloseProps } from "./dialog-close";
+export type { DialogPortalProps } from "./dialog-portal";
+export type { DialogOverlayProps } from "./dialog-overlay";
diff --git a/packages/core/src/primitives/create-disclosure-state.ts b/packages/core/src/primitives/create-disclosure-state.ts
index 59c1470..7e9a6b0 100644
--- a/packages/core/src/primitives/create-disclosure-state.ts
+++ b/packages/core/src/primitives/create-disclosure-state.ts
@@ -25,7 +25,7 @@ export function createDisclosureState(
   const [isOpen, setIsOpen] = createControllableSignal<boolean>({
     value: () => options.open,
     defaultValue: () => options.defaultOpen ?? false,
-    onChange: options.onOpenChange,
+    ...(options.onOpenChange !== undefined && { onChange: options.onOpenChange }),
   });
 
   return {
diff --git a/packages/core/src/utilities/presence/presence.tsx b/packages/core/src/utilities/presence/presence.tsx
index 169bb78..1d008f4 100644
--- a/packages/core/src/utilities/presence/presence.tsx
+++ b/packages/core/src/utilities/presence/presence.tsx
@@ -75,11 +75,12 @@ export function Presence(props: PresenceProps): JSX.Element {
   // Wrap in a function so Show evaluates children lazily (only when mounted).
   return (
     <Show when={shouldMount()}>
-      {() =>
-        typeof props.children === "function"
-          ? (props.children as (p: PresenceChildProps) => JSX.Element)(childProps)
-          : props.children
-      }
+      {(
+        () =>
+          typeof props.children === "function"
+            ? (props.children as (p: PresenceChildProps) => JSX.Element)(childProps)
+            : props.children
+      ) as unknown as JSX.Element}
     </Show>
   );
 }
diff --git a/packages/core/tests/components/dialog/dialog-rendering.test.tsx b/packages/core/tests/components/dialog/dialog-rendering.test.tsx
new file mode 100644
index 0000000..2b159c7
--- /dev/null
+++ b/packages/core/tests/components/dialog/dialog-rendering.test.tsx
@@ -0,0 +1,65 @@
+// packages/core/tests/components/dialog/dialog-rendering.test.tsx
+import { render, screen } from "@solidjs/testing-library";
+import { createSignal } from "solid-js";
+import { describe, expect, it } from "vitest";
+import { Dialog } from "../../../src/components/dialog/index";
+
+describe("Dialog rendering", () => {
+  it("renders children", () => {
+    render(() => (
+      <Dialog defaultOpen>
+        <Dialog.Content>
+          <Dialog.Title>Hello</Dialog.Title>
+        </Dialog.Content>
+      </Dialog>
+    ));
+    expect(screen.getByText("Hello")).toBeTruthy();
+  });
+
+  it("does not render content when closed by default", () => {
+    render(() => (
+      <Dialog>
+        <Dialog.Content>
+          <Dialog.Title>Hidden</Dialog.Title>
+        </Dialog.Content>
+      </Dialog>
+    ));
+    expect(screen.queryByText("Hidden")).toBeNull();
+  });
+
+  it("renders content when defaultOpen is true", () => {
+    render(() => (
+      <Dialog defaultOpen>
+        <Dialog.Content>
+          <Dialog.Title>Visible</Dialog.Title>
+        </Dialog.Content>
+      </Dialog>
+    ));
+    expect(screen.getByText("Visible")).toBeTruthy();
+  });
+
+  it("renders content when controlled open is true", () => {
+    render(() => (
+      <Dialog open={true} onOpenChange={() => {}}>
+        <Dialog.Content>
+          <Dialog.Title>Controlled</Dialog.Title>
+        </Dialog.Content>
+      </Dialog>
+    ));
+    expect(screen.getByText("Controlled")).toBeTruthy();
+  });
+
+  it("closes when controlled open is set to false", () => {
+    const [open, setOpen] = createSignal(true);
+    render(() => (
+      <Dialog open={open()} onOpenChange={setOpen}>
+        <Dialog.Content>
+          <Dialog.Title>Toggled</Dialog.Title>
+        </Dialog.Content>
+      </Dialog>
+    ));
+    expect(screen.getByText("Toggled")).toBeTruthy();
+    setOpen(false);
+    expect(screen.queryByText("Toggled")).toBeNull();
+  });
+});
diff --git a/tsconfig.base.json b/tsconfig.base.json
index 3fd4bf8..56ad17e 100644
--- a/tsconfig.base.json
+++ b/tsconfig.base.json
@@ -13,6 +13,7 @@
     "declarationMap": true,
     "sourceMap": true,
     "esModuleInterop": false,
-    "skipLibCheck": true
+    "skipLibCheck": true,
+    "ignoreDeprecations": "6.0"
   }
 }