diff --git a/client/src/blocks/BlockRenderer.jsx b/client/src/blocks/BlockRenderer.jsx
new file mode 100644
index 0000000..e78e94f
--- /dev/null
+++ b/client/src/blocks/BlockRenderer.jsx
@@ -0,0 +1,26 @@
+// Renders stored blocks via their registry component. Used by the public page
+// route, the draft preview, and (recursively) the two_column block. Kept
+// separate from the registry so both the renderer and the builder can import it.
+// Import the lookup from the registry directly (not ./index) to avoid a cycle:
+// index → types/twoColumn → BlockRenderer. The page route/builder import ./index,
+// which registers every block before anything renders.
+import { getBlock } from './registry.js'
+
+/**
+ * Render one block. A block with `visible === false` renders nothing (admins
+ * hide blocks without deleting them). An unknown type also renders nothing —
+ * server validation prevents storing one, so this only guards a client/server
+ * registry skew rather than crashing the whole page.
+ */
+export default function BlockRenderer({ block }) {
+  if (!block || block.visible === false) return null
+  const def = getBlock(block.type)
+  if (!def || !def.component) return null
+  const Component = def.component
+  return <Component props={block.props || {}} block={block} />
+}
+
+/** Render an ordered array of blocks (array position = display order). */
+export function BlockList({ blocks }) {
+  return (blocks || []).map((block) => <BlockRenderer key={block.id} block={block} />)
+}
diff --git a/client/src/blocks/editorKit.jsx b/client/src/blocks/editorKit.jsx
new file mode 100644
index 0000000..481fb21
--- /dev/null
+++ b/client/src/blocks/editorKit.jsx
@@ -0,0 +1,64 @@
+// Shared form controls for block editors, styled with the existing admin design
+// system (.field-label / .input / .select). Every block's editor is a
+// ({ props, onChange }) component; these keep the seven of them consistent and
+// short. onChange always receives the full next props object.
+
+export function Field({ label, hint, children }) {
+  return (
+    <label style={{ display: 'block' }}>
+      <span className="field-label">{label}</span>
+      {children}
+      {hint && (
+        <span className="sans dim" style={{ display: 'block', fontSize: '0.78rem', marginTop: 4 }}>
+          {hint}
+        </span>
+      )}
+    </label>
+  )
+}
+
+export function TextField({ label, hint, value, onChange, placeholder, maxLength }) {
+  return (
+    <Field label={label} hint={hint}>
+      <input
+        type="text"
+        className="input"
+        value={value ?? ''}
+        placeholder={placeholder}
+        maxLength={maxLength}
+        onChange={(e) => onChange(e.target.value)}
+      />
+    </Field>
+  )
+}
+
+export function TextAreaField({ label, hint, value, onChange, placeholder, rows = 4, maxLength }) {
+  return (
+    <Field label={label} hint={hint}>
+      <textarea
+        className="input"
+        rows={rows}
+        value={value ?? ''}
+        placeholder={placeholder}
+        maxLength={maxLength}
+        onChange={(e) => onChange(e.target.value)}
+        style={{ resize: 'vertical', fontFamily: 'inherit' }}
+      />
+    </Field>
+  )
+}
+
+// options: array of [value, label] tuples.
+export function SelectField({ label, hint, value, onChange, options }) {
+  return (
+    <Field label={label} hint={hint}>
+      <select className="select" value={value ?? ''} onChange={(e) => onChange(e.target.value)}>
+        {options.map(([v, l]) => (
+          <option key={v} value={v}>
+            {l}
+          </option>
+        ))}
+      </select>
+    </Field>
+  )
+}
diff --git a/client/src/blocks/index.js b/client/src/blocks/index.js
index 6d7f95d..67f504f 100644
--- a/client/src/blocks/index.js
+++ b/client/src/blocks/index.js
@@ -9,11 +9,11 @@
 
 export * from './registry'
 
-// ── Wave 1 block definitions ──────────────────────────────────────────
-// import './types/heading'    // added in step 3
-// import './types/richText'
-// import './types/image'
-// import './types/twoColumn'
-// import './types/cta'
-// import './types/divider'
-// import './types/quote'
+// ── Wave 1 block definitions (self-register on import) ─────────────────
+import './types/heading.jsx'
+import './types/richText.jsx'
+import './types/image.jsx'
+import './types/twoColumn.jsx'
+import './types/cta.jsx'
+import './types/divider.jsx'
+import './types/quote.jsx'
diff --git a/client/src/blocks/types/cta.jsx b/client/src/blocks/types/cta.jsx
new file mode 100644
index 0000000..9511ff0
--- /dev/null
+++ b/client/src/blocks/types/cta.jsx
@@ -0,0 +1,63 @@
+// cta block — a call-to-action button/link. Renders as an anchor styled with the
+// existing button system (primary / secondary).
+import { registerBlock } from '../registry'
+import { SelectField, TextField } from '../editorKit.jsx'
+
+const STYLES = [
+  ['primary', 'Primary'],
+  ['secondary', 'Secondary'],
+]
+
+function CtaBlock({ props }) {
+  if (!props.url || !props.text) return null
+  const style = props.style === 'secondary' ? 'secondary' : 'primary'
+  // External links get a safe rel; same-origin relative links don't need it.
+  const external = /^https?:\/\//i.test(props.url)
+  return (
+    <div className="page-cta-wrap">
+      <a
+        className={`btn btn-sq page-cta page-cta--${style}`}
+        href={props.url}
+        {...(external ? { rel: 'noopener noreferrer nofollow' } : {})}
+      >
+        {props.text}
+      </a>
+    </div>
+  )
+}
+
+function CtaEditor({ props, onChange }) {
+  return (
+    <div style={{ display: 'flex', flexDirection: 'column', gap: 12 }}>
+      <TextField
+        label="Button text"
+        value={props.text}
+        maxLength={100}
+        onChange={(text) => onChange({ ...props, text })}
+      />
+      <TextField
+        label="URL"
+        hint="A full https:// link or a same-site path like /wiki/getting-started."
+        value={props.url}
+        placeholder="https://…"
+        onChange={(url) => onChange({ ...props, url })}
+      />
+      <SelectField
+        label="Style"
+        value={props.style || 'primary'}
+        onChange={(style) => onChange({ ...props, style })}
+        options={STYLES}
+      />
+    </div>
+  )
+}
+
+registerBlock({
+  type: 'cta',
+  version: 1,
+  label: 'Button',
+  icon: '⇥',
+  component: CtaBlock,
+  editor: CtaEditor,
+  defaults: () => ({ text: '', url: '', style: 'primary' }),
+})
diff --git a/client/src/blocks/types/divider.jsx b/client/src/blocks/types/divider.jsx
new file mode 100644
index 0000000..fd1f9d6
--- /dev/null
+++ b/client/src/blocks/types/divider.jsx
@@ -0,0 +1,25 @@
+// divider block — a pure spacer / horizontal rule. No props, so its editor is
+// just a note.
+import { registerBlock } from '../registry'
+
+function DividerBlock() {
+  return <hr className="page-divider" />
+}
+
+function DividerEditor() {
+  return (
+    <p className="sans dim" style={{ margin: 0, fontSize: '0.85rem' }}>
+      A divider has no options — it adds a horizontal rule and spacing.
+    </p>
+  )
+}
+
+registerBlock({
+  type: 'divider',
+  version: 1,
+  label: 'Divider',
+  icon: '—',
+  component: DividerBlock,
+  editor: DividerEditor,
+  defaults: () => ({}),
+})
diff --git a/client/src/blocks/types/heading.jsx b/client/src/blocks/types/heading.jsx
new file mode 100644
index 0000000..81be8b4
--- /dev/null
+++ b/client/src/blocks/types/heading.jsx
@@ -0,0 +1,46 @@
+// heading block — plain-text section heading (h1–h4). Text is rendered as text
+// (React escapes it); use rich_text for inline markup.
+import { registerBlock } from '../registry'
+import { SelectField, TextField } from '../editorKit.jsx'
+
+const LEVELS = [
+  ['h1', 'Heading 1'],
+  ['h2', 'Heading 2'],
+  ['h3', 'Heading 3'],
+  ['h4', 'Heading 4'],
+]
+const VALID = ['h1', 'h2', 'h3', 'h4']
+
+function HeadingBlock({ props }) {
+  const Tag = VALID.includes(props.level) ? props.level : 'h2'
+  return <Tag className="page-heading">{props.text}</Tag>
+}
+
+function HeadingEditor({ props, onChange }) {
+  return (
+    <div style={{ display: 'flex', flexDirection: 'column', gap: 12 }}>
+      <SelectField
+        label="Level"
+        value={props.level || 'h2'}
+        onChange={(level) => onChange({ ...props, level })}
+        options={LEVELS}
+      />
+      <TextField
+        label="Text"
+        value={props.text}
+        maxLength={200}
+        onChange={(text) => onChange({ ...props, text })}
+      />
+    </div>
+  )
+}
+
+registerBlock({
+  type: 'heading',
+  version: 1,
+  label: 'Heading',
+  icon: 'H',
+  component: HeadingBlock,
+  editor: HeadingEditor,
+  defaults: () => ({ level: 'h2', text: '' }),
+})
diff --git a/client/src/blocks/types/image.jsx b/client/src/blocks/types/image.jsx
new file mode 100644
index 0000000..217ee14
--- /dev/null
+++ b/client/src/blocks/types/image.jsx
@@ -0,0 +1,100 @@
+// image block — a single image with optional caption and alignment. Upload
+// reuses the shared admin uploader (returns { url }); the block stays URL-based
+// until the Wave 3 asset picker lands.
+import { useState } from 'react'
+import { registerBlock } from '../registry'
+import { api } from '../../api/client.js'
+import { SelectField, TextField } from '../editorKit.jsx'
+
+const ALIGN = [
+  ['left', 'Left'],
+  ['center', 'Center'],
+  ['right', 'Right'],
+  ['full', 'Full width'],
+]
+const VALID = ['left', 'center', 'right', 'full']
+
+function ImageBlock({ props }) {
+  if (!props.src) return null
+  const align = VALID.includes(props.alignment) ? props.alignment : 'center'
+  return (
+    <figure className={`page-image page-image--${align}`}>
+      <img src={props.src} alt={props.alt || ''} />
+      {props.caption && <figcaption>{props.caption}</figcaption>}
+    </figure>
+  )
+}
+
+function ImageEditor({ props, onChange }) {
+  const [uploading, setUploading] = useState(false)
+  const [error, setError] = useState('')
+
+  async function onUpload(e) {
+    const file = e.target.files?.[0]
+    e.target.value = ''
+    if (!file) return
+    setUploading(true)
+    setError('')
+    try {
+      const { url } = await api.admin.upload(file)
+      onChange({ ...props, src: url })
+    } catch (err) {
+      setError(err.message || 'Upload failed')
+    } finally {
+      setUploading(false)
+    }
+  }
+
+  return (
+    <div style={{ display: 'flex', flexDirection: 'column', gap: 12 }}>
+      <div>
+        <span className="field-label">Image</span>
+        <input
+          type="file"
+          accept="image/*"
+          onChange={onUpload}
+          className="sans"
+          style={{ color: 'var(--muted)', fontSize: '0.85rem', display: 'block' }}
+        />
+        {uploading && <span className="sans dim" style={{ fontSize: '0.8rem' }}> uploading…</span>}
+        {error && <span className="sans" style={{ fontSize: '0.8rem', color: '#d98b84' }}>{error}</span>}
+        {props.src && (
+          <img
+            src={props.src}
+            alt=""
+            style={{ display: 'block', marginTop: 10, maxWidth: '100%', borderRadius: 8, border: '1px solid var(--line)' }}
+          />
+        )}
+      </div>
+      <TextField
+        label="Alt text"
+        hint="Describes the image for screen readers and when it fails to load."
+        value={props.alt}
+        maxLength={300}
+        onChange={(alt) => onChange({ ...props, alt })}
+      />
+      <TextField
+        label="Caption (optional)"
+        value={props.caption}
+        maxLength={500}
+        onChange={(caption) => onChange({ ...props, caption })}
+      />
+      <SelectField
+        label="Alignment"
+        value={props.alignment || 'center'}
+        onChange={(alignment) => onChange({ ...props, alignment })}
+        options={ALIGN}
+      />
+    </div>
+  )
+}
+
+registerBlock({
+  type: 'image',
+  version: 1,
+  label: 'Image',
+  icon: '🖼',
+  component: ImageBlock,
+  editor: ImageEditor,
+  defaults: () => ({ src: '', alt: '', caption: '', alignment: 'center' }),
+})
diff --git a/client/src/blocks/types/quote.jsx b/client/src/blocks/types/quote.jsx
new file mode 100644
index 0000000..46cc657
--- /dev/null
+++ b/client/src/blocks/types/quote.jsx
@@ -0,0 +1,43 @@
+// quote block — a pull quote with optional attribution.
+import { registerBlock } from '../registry'
+import { TextAreaField, TextField } from '../editorKit.jsx'
+
+function QuoteBlock({ props }) {
+  if (!props.text) return null
+  return (
+    <figure className="page-quote">
+      <blockquote>{props.text}</blockquote>
+      {props.attribution && <figcaption>— {props.attribution}</figcaption>}
+    </figure>
+  )
+}
+
+function QuoteEditor({ props, onChange }) {
+  return (
+    <div style={{ display: 'flex', flexDirection: 'column', gap: 12 }}>
+      <TextAreaField
+        label="Quote"
+        value={props.text}
+        rows={3}
+        maxLength={1000}
+        onChange={(text) => onChange({ ...props, text })}
+      />
+      <TextField
+        label="Attribution (optional)"
+        value={props.attribution}
+        maxLength={200}
+        onChange={(attribution) => onChange({ ...props, attribution })}
+      />
+    </div>
+  )
+}
+
+registerBlock({
+  type: 'quote',
+  version: 1,
+  label: 'Quote',
+  icon: '❝',
+  component: QuoteBlock,
+  editor: QuoteEditor,
+  defaults: () => ({ text: '', attribution: '' }),
+})
diff --git a/client/src/blocks/types/richText.jsx b/client/src/blocks/types/richText.jsx
new file mode 100644
index 0000000..78b6e05
--- /dev/null
+++ b/client/src/blocks/types/richText.jsx
@@ -0,0 +1,39 @@
+// rich_text block — HTML from the shared rich-text editor. Rendered inside the
+// same `.prose` styling as wiki/news bodies, sanitized on render as defense in
+// depth (the server also sanitizes on save).
+import { lazy, Suspense } from 'react'
+import DOMPurify from 'dompurify'
+import { registerBlock } from '../registry'
+
+const RichTextEditor = lazy(() => import('../../components/RichTextEditor.jsx'))
+
+function RichTextBlock({ props }) {
+  return (
+    <div
+      className="prose page-rich-text"
+      dangerouslySetInnerHTML={{ __html: DOMPurify.sanitize(props.html || '') }}
+    />
+  )
+}
+
+function RichTextEditorForm({ props, onChange }) {
+  return (
+    <Suspense fallback={<span className="spin" />}>
+      <RichTextEditor
+        value={props.html || ''}
+        onChange={(html) => onChange({ ...props, html })}
+        variant="post"
+      />
+    </Suspense>
+  )
+}
+
+registerBlock({
+  type: 'rich_text',
+  version: 1,
+  label: 'Rich text',
+  icon: '¶',
+  component: RichTextBlock,
+  editor: RichTextEditorForm,
+  defaults: () => ({ html: '' }),
+})
diff --git a/client/src/blocks/types/twoColumn.jsx b/client/src/blocks/types/twoColumn.jsx
new file mode 100644
index 0000000..cf5a998
--- /dev/null
+++ b/client/src/blocks/types/twoColumn.jsx
@@ -0,0 +1,120 @@
+// two_column block — the only container. Holds two ordered arrays of sub-blocks
+// (`left`, `right`). Sub-blocks are leaf blocks only (no nested containers — the
+// one-level cap the server also enforces), so the column editor's palette is the
+// set of non-container registered blocks.
+import { registerBlock, getBlock, listBlocks, makeBlockId } from '../registry'
+import BlockRenderer from '../BlockRenderer.jsx'
+
+// ── Renderer ──────────────────────────────────────────────────────────
+function TwoColumnBlock({ props }) {
+  const left = Array.isArray(props.left) ? props.left : []
+  const right = Array.isArray(props.right) ? props.right : []
+  return (
+    <div className="page-two-column">
+      <div className="page-column">
+        {left.map((b) => (
+          <BlockRenderer key={b.id} block={b} />
+        ))}
+      </div>
+      <div className="page-column">
+        {right.map((b) => (
+          <BlockRenderer key={b.id} block={b} />
+        ))}
+      </div>
+    </div>
+  )
+}
+
+// ── Column editor ─────────────────────────────────────────────────────
+// Manages one side's array: add (from the leaf palette), edit each via its own
+// registry editor, reorder, remove.
+function ColumnEditor({ title, items, onChange }) {
+  const list = Array.isArray(items) ? items : []
+  const palette = listBlocks().filter((b) => !b.container)
+
+  function addBlock(type) {
+    const def = getBlock(type)
+    if (!def) return
+    const block = { id: makeBlockId(), type, version: def.version, visible: true, props: def.defaults() }
+    onChange([...list, block])
+  }
+  function updateAt(i, nextProps) {
+    onChange(list.map((b, j) => (j === i ? { ...b, props: nextProps } : b)))
+  }
+  function removeAt(i) {
+    onChange(list.filter((_, j) => j !== i))
+  }
+  function move(i, dir) {
+    const j = i + dir
+    if (j < 0 || j >= list.length) return
+    const next = [...list]
+    ;[next[i], next[j]] = [next[j], next[i]]
+    onChange(next)
+  }
+
+  return (
+    <div className="pb-column-editor">
+      <div className="pb-column-head">
+        <span className="field-label" style={{ margin: 0 }}>{title}</span>
+        <select
+          className="select pb-add-select"
+          value=""
+          onChange={(e) => {
+            if (e.target.value) addBlock(e.target.value)
+            e.target.value = ''
+          }}
+        >
+          <option value="">+ Add block…</option>
+          {palette.map((b) => (
+            <option key={b.type} value={b.type}>
+              {b.label}
+            </option>
+          ))}
+        </select>
+      </div>
+
+      {list.length === 0 && (
+        <p className="sans dim" style={{ fontSize: '0.8rem', margin: '4px 0' }}>Empty column.</p>
+      )}
+
+      {list.map((block, i) => {
+        const def = getBlock(block.type)
+        const Editor = def?.editor
+        return (
+          <div key={block.id} className="pb-subblock">
+            <div className="pb-subblock-head">
+              <span className="sans dim" style={{ fontSize: '0.78rem' }}>{def?.label || block.type}</span>
+              <div className="pb-subblock-actions">
+                <button type="button" className="pill pb-mini" disabled={i === 0} onClick={() => move(i, -1)} title="Move up">↑</button>
+                <button type="button" className="pill pb-mini" disabled={i === list.length - 1} onClick={() => move(i, 1)} title="Move down">↓</button>
+                <button type="button" className="pill pb-mini" onClick={() => removeAt(i)} title="Remove">✕</button>
+              </div>
+            </div>
+            {Editor && <Editor props={block.props || {}} onChange={(p) => updateAt(i, p)} />}
+          </div>
+        )
+      })}
+    </div>
+  )
+}
+
+function TwoColumnEditor({ props, onChange }) {
+  return (
+    <div className="pb-two-column-editor">
+      <ColumnEditor title="Left column" items={props.left} onChange={(left) => onChange({ ...props, left })} />
+      <ColumnEditor title="Right column" items={props.right} onChange={(right) => onChange({ ...props, right })} />
+    </div>
+  )
+}
+
+registerBlock({
+  type: 'two_column',
+  version: 1,
+  label: 'Two columns',
+  icon: '▥',
+  component: TwoColumnBlock,
+  editor: TwoColumnEditor,
+  defaults: () => ({ left: [], right: [] }),
+  container: true,
+  containerSlots: ['left', 'right'],
+})
diff --git a/client/src/styles/theme.css b/client/src/styles/theme.css
index 23d9331..55dac7a 100644
--- a/client/src/styles/theme.css
+++ b/client/src/styles/theme.css
@@ -740,3 +740,147 @@ button[disabled] {
     grid-template-columns: 1fr;
   }
 }
+
+/* ===== CMS page builder — public block rendering ===== */
+/* Vertical rhythm between top-level blocks on a rendered page. */
+.page-blocks > * + * {
+  margin-top: 26px;
+}
+.page-heading {
+  font-family: var(--serif, Georgia, serif);
+  color: var(--ink);
+  line-height: 1.2;
+}
+.page-divider {
+  border: none;
+  border-top: 1px solid var(--line);
+  margin: 8px 0;
+}
+/* image block */
+.page-image {
+  margin: 0;
+}
+.page-image img {
+  max-width: 100%;
+  border-radius: 8px;
+  border: 1px solid var(--line);
+  display: block;
+}
+.page-image figcaption {
+  margin-top: 8px;
+  color: var(--muted);
+  font-family: var(--sans);
+  font-size: 0.82rem;
+}
+.page-image--center {
+  text-align: center;
+}
+.page-image--center img,
+.page-image--center figcaption {
+  margin-left: auto;
+  margin-right: auto;
+}
+.page-image--right {
+  text-align: right;
+}
+.page-image--right img,
+.page-image--right figcaption {
+  margin-left: auto;
+}
+.page-image--full img {
+  width: 100%;
+}
+/* cta block */
+.page-cta-wrap {
+  display: flex;
+}
+.page-cta--secondary {
+  background: transparent;
+  color: var(--ink);
+}
+/* quote block */
+.page-quote {
+  margin: 0;
+  border-left: 3px solid var(--accent);
+  padding: 4px 0 4px 20px;
+}
+.page-quote blockquote {
+  margin: 0;
+  font-size: 1.15rem;
+  line-height: 1.5;
+  color: var(--ink);
+  font-style: italic;
+}
+.page-quote figcaption {
+  margin-top: 8px;
+  color: var(--muted);
+  font-family: var(--sans);
+  font-size: 0.85rem;
+}
+/* two-column block */
+.page-two-column {
+  display: grid;
+  grid-template-columns: 1fr 1fr;
+  gap: 32px;
+}
+.page-column > * + * {
+  margin-top: 18px;
+}
+@media (max-width: 720px) {
+  .page-two-column {
+    grid-template-columns: 1fr;
+  }
+}
+
+/* ===== CMS page builder — column sub-block editor ===== */
+.pb-two-column-editor {
+  display: grid;
+  grid-template-columns: 1fr 1fr;
+  gap: 16px;
+}
+@media (max-width: 720px) {
+  .pb-two-column-editor {
+    grid-template-columns: 1fr;
+  }
+}
+.pb-column-editor {
+  border: 1px solid var(--line);
+  border-radius: 8px;
+  padding: 12px;
+  background: var(--panel-flat, transparent);
+}
+.pb-column-head {
+  display: flex;
+  align-items: center;
+  justify-content: space-between;
+  gap: 8px;
+  margin-bottom: 10px;
+}
+.pb-add-select {
+  width: auto;
+  padding: 6px 10px;
+  font-size: 0.82rem;
+}
+.pb-subblock {
+  border: 1px solid var(--line);
+  border-radius: 8px;
+  padding: 10px;
+  margin-top: 10px;
+  background: var(--bg);
+}
+.pb-subblock-head {
+  display: flex;
+  align-items: center;
+  justify-content: space-between;
+  margin-bottom: 8px;
+}
+.pb-subblock-actions {
+  display: flex;
+  gap: 4px;
+}
+.pb-mini {
+  min-width: 28px;
+  padding: 3px 8px;
+  font-size: 0.8rem;
+  line-height: 1;
+}