diff --git a/examples/structured-document.tsx b/examples/structured-document.tsx
new file mode 100644
index 0000000..9c3e236
--- /dev/null
+++ b/examples/structured-document.tsx
@@ -0,0 +1,17 @@
+// deno-lint-ignore-file jsx-key
+/** @jsx Docx.jsx */
+
+import Docx, { Paragraph, StructuredDocument, Text } from '../mod.ts';
+
+await Docx.fromJsx([
+	<StructuredDocument alias='test' appearance='hidden'>
+		<Paragraph>
+			<Text>Content</Text>
+		</Paragraph>
+		<StructuredDocument alias='nested' lock='sdtLocked'>
+			<Paragraph>
+				<Text>More Content</Text>
+			</Paragraph>
+		</StructuredDocument>
+	</StructuredDocument>,
+]).toFile('structured-document.docx');
diff --git a/lib/components/document/src/Section.ts b/lib/components/document/src/Section.ts
index 379fec4..abf8151 100644
--- a/lib/components/document/src/Section.ts
+++ b/lib/components/document/src/Section.ts
@@ -26,7 +26,7 @@ import type { MoveFrom } from '../../track-changes/src/MoveFrom.ts';
 import type { MoveTo } from '../../track-changes/src/MoveTo.ts';
 import type { BookmarkRangeEnd } from './BookmarkRangeEnd.ts';
 import type { BookmarkRangeStart } from './BookmarkRangeStart.ts';
-import { Paragraph } from './Paragraph.ts';
+import type { Paragraph } from './Paragraph.ts';
 import type { Table } from './Table.ts';
 
 /**
diff --git a/lib/components/document/src/StructuredDocument.ts b/lib/components/document/src/StructuredDocument.ts
new file mode 100644
index 0000000..43a4e65
--- /dev/null
+++ b/lib/components/document/src/StructuredDocument.ts
@@ -0,0 +1,155 @@
+// Import without assignment ensures Deno does not tree-shake this component. To avoid circular
+// definitions, components register themselves in a side-effect of their module.
+// import './Paragraph.ts'; // ?????????????
+
+import {
+	Component,
+	type ComponentAncestor,
+} from '../../../classes/src/Component.ts';
+import { registerComponent } from '../../../utilities/src/components.ts';
+import { create } from '../../../utilities/src/dom.ts';
+import { QNS } from '../../../utilities/src/namespaces.ts';
+import type { Deletion } from '../../track-changes/src/Deletion.ts';
+import type { Insertion } from '../../track-changes/src/Insertion.ts';
+import type { MoveFrom } from '../../track-changes/src/MoveFrom.ts';
+import type { MoveFromRangeEnd } from '../../track-changes/src/MoveFromRangeEnd.ts';
+import type { MoveFromRangeStart } from '../../track-changes/src/MoveFromRangeStart.ts';
+import type { MoveTo } from '../../track-changes/src/MoveTo.ts';
+import type { MoveToRangeEnd } from '../../track-changes/src/MoveToRangeEnd.ts';
+import type { MoveToRangeStart } from '../../track-changes/src/MoveToRangeStart.ts';
+import type { BookmarkRangeEnd } from './BookmarkRangeEnd.ts';
+import type { BookmarkRangeStart } from './BookmarkRangeStart.ts';
+import type { Paragraph } from './Paragraph.ts';
+import type { Table } from './Table.ts';
+
+/**
+ * A type describing the components accepted as children of {@link }.
+ */
+export type StructuredDocumentChild =
+	| Paragraph
+	| Table
+	| BookmarkRangeStart
+	| BookmarkRangeEnd
+	| MoveTo
+	| MoveFrom
+	| MoveToRangeStart
+	| MoveToRangeEnd
+	| MoveFromRangeStart
+	| MoveFromRangeEnd
+	| Insertion
+	| Deletion
+	| StructuredDocument;
+
+/**
+ * A type describing the props accepted by {@link }.
+ */
+export type StructuredDocumentProps = {
+	/**
+	 * Controls how the structured document tag (content control) is rendered in Word.
+	 *
+	 * This maps to the `w15:appearance` element (Word 2013+ extension). Possible values:
+	 * - `boundingBox` — the default; shows the control's blue bounding box with a title tab.
+	 * - `tags` — shows start/end tag markers around the content.
+	 * - `hidden` — shows no decoration at all (no box, no tags).
+	 *
+	 * @see https://learn.microsoft.com/en-us/dotnet/api/documentformat.openxml.office2013.word.sdtappearance
+	 */
+	appearance?: 'boundingBox' | 'tags' | 'hidden' | null;
+	/**
+	 * Friendly name associated with the current structured document tag.
+	 */
+	alias?: string | null;
+	/**
+	 * Set of behaviors which shall be applied to the contents of the parent structured document tag
+	 * when the contents of this documents are edited
+	 *
+	 * @see https://c-rex.net/samples/ooxml/e1/Part4/OOXML_P4_DOCX_lock_topic_ID0EN6PS.html#topic_ID0EN6PS
+	 */
+	lock?: // Contents Cannot Be Edited At Runtime
+		| 'contentLocked'
+		// Contents Cannot Be Edited At Runtime And SDT Cannot Be Deleted
+		| 'sdtContentLocked'
+		// SDT Cannot Be Deleted
+		| 'sdtLocked'
+		// No Locking.  Used by Word by default.
+		| 'unlocked'
+		| null;
+};
+
+/**
+ *
+ */
+export class StructuredDocument extends Component<
+	StructuredDocumentProps,
+	StructuredDocumentChild
+> {
+	public static override readonly children: string[] = [
+		'Paragraph',
+		'Table',
+		'BookmarkRangeEnd',
+		'BookmarkRangeStart',
+		'MoveTo',
+		'MoveFrom',
+		'MoveToRangeStart',
+		'MoveToRangeEnd',
+		'MoveFromRangeStart',
+		'MoveFromRangeEnd',
+		'Insertion',
+		'Deletion',
+		'StructuredDocument',
+	];
+	public static override readonly mixed: boolean = false;
+
+	/**
+	 * Creates an XML DOM node for this component instance.
+	 */
+	public override async toNode(ancestry: ComponentAncestor[]): Promise<Node> {
+		const properties = create(
+			`
+                element ${QNS.w}sdtPr {
+                    if (exists($appearance)) then element ${QNS.w15}appearance {
+                        attribute ${QNS.w15}val { $appearance }
+                    } else (),
+                    if (exists($alias)) then element ${QNS.w}alias {
+                        attribute ${QNS.w}val { $alias }
+                    } else (),
+                    if (exists($lock)) then element ${QNS.w}lock {
+                        attribute ${QNS.w}val { $lock }
+                    } else ()
+                }
+            `,
+			{
+				appearance: this.props.appearance || null,
+				alias: this.props.alias || null,
+				lock: this.props.lock || null,
+			}
+		);
+		return create(
+			`
+                element ${QNS.w}sdt {
+                    $stdPr,
+                    element ${QNS.w}sdtContent {
+                        $children
+                    }
+                }
+            `,
+			{ stdPr: properties, children: await this.childrenToNode(ancestry) }
+		);
+	}
+
+	/**
+	 * Asserts whether or not a given XML node correlates with this component.
+	 */
+	static override matchesNode(node: Node): boolean {
+		return node.nodeName === 'w:sdt';
+	}
+
+	/**
+	 * Instantiate this component from the XML in an existing DOCX file.
+	 */
+	static override fromNode(): StructuredDocument {
+		return new StructuredDocument({});
+	}
+}
+
+registerComponent(StructuredDocument);
diff --git a/mod.ts b/mod.ts
index 3424ab5..e84fa40 100644
--- a/mod.ts
+++ b/mod.ts
@@ -135,6 +135,11 @@ export {
 	type SectionChild,
 	type SectionProps,
 } from './lib/components/document/src/Section.ts';
+export {
+	StructuredDocument,
+	type StructuredDocumentChild,
+	type StructuredDocumentProps,
+} from './lib/components/document/src/StructuredDocument.ts';
 export {
 	Symbol,
 	type SymbolChild,