diff --git a/app/scaling/components/Progress.tsx b/app/scaling/components/Progress.tsx
new file mode 100644
index 0000000..15451ae
--- /dev/null
+++ b/app/scaling/components/Progress.tsx
@@ -0,0 +1,62 @@
+import { Card } from '../../components/ui/Card';
+import { EmptyState } from '../../components/ui/EmptyState';
+import { Text } from '../../components/ui/Text';
+import type { WorkItem } from '../snapshot.mjs';
+import { Info } from './Info';
+import { Tag } from './Tag';
+
+export function Progress({ work }: { work: WorkItem[] }) {
+  return (
+    <section className="flex flex-col gap-3">
+      <Text as="h2" variant="headline">Progress</Text>
+      {work.length === 0 ? (
+        <EmptyState description="No current work supplied for this snapshot." />
+      ) : (
+        <Card className="divide-y divide-bds-gray-10 bg-background text-[13px] dark:divide-white/10 dark:bg-white/5">
+          {work.map((w) => <Row key={w.title} item={w} />)}
+        </Card>
+      )}
+      <Text variant="footnote" tone="muted">Expected effects are not summed.</Text>
+    </section>
+  );
+}
+
+function Row({ item: w }: { item: WorkItem }) {
+  const l = w.linear;
+  return (
+    <div className="flex flex-col gap-2 px-4 py-3">
+      <span className="flex flex-wrap items-center gap-2">
+        <Text as="span" variant="label">{w.title}</Text>
+        <Info label={`About ${w.title}`}>
+          <p>Hypothesis: {w.hypothesis}</p>
+          <p>Change: {w.change}</p>
+          <p>Owner: {w.owner ?? 'none assigned'}</p>
+        </Info>
+        <Tag tag={w.area} />
+        <Tag tag={l ? l.state : 'proposed'} />
+      </span>
+      {l ? (
+        <span className="flex items-center gap-2">
+          <span
+            role="progressbar"
+            aria-label={`${l.scopeDone} of ${l.scopeTotal} issues done`}
+            aria-valuemin={0}
+            aria-valuemax={l.scopeTotal}
+            aria-valuenow={l.scopeDone}
+            className="h-1.5 w-40 overflow-hidden rounded-full bg-bds-gray-10 dark:bg-white/10"
+          >
+            <span className="block h-full bg-base-blue" style={{ width: `${l.scopeTotal ? (100 * l.scopeDone) / l.scopeTotal : 0}%` }} />
+          </span>
+          <span className="font-mono text-[12px] text-bds-gray-60">{l.scopeDone}/{l.scopeTotal}</span>
+        </span>
+      ) : null}
+      <p><span className="text-bds-gray-60">Expected:</span> {w.expected ?? 'Not estimated'}</p>
+      {w.evidence && w.realized ? <p><span className="text-bds-gray-60">Realized:</span> {w.realized}</p> : null}
+      <div className="flex flex-wrap gap-3">
+        {[w.evidence, l && { label: 'Linear', url: l.url }, ...w.links].map((link) => link ? (
+          <a key={link.url} className="w-fit underline" href={link.url} target="_blank" rel="noreferrer">{link.label}</a>
+        ) : null)}
+      </div>
+    </div>
+  );
+}
diff --git a/app/scaling/components/Tag.tsx b/app/scaling/components/Tag.tsx
index 5fe623d..cb83d08 100644
--- a/app/scaling/components/Tag.tsx
+++ b/app/scaling/components/Tag.tsx
@@ -2,6 +2,7 @@ const LABEL: Record<string, string> = {
   measured: 'Measured', modeled: 'Modeled', estimated: 'Estimated',
   'not-measured': 'Not measured', 'not-modeled': 'Not modeled', 'not-established': 'Not established',
   provisional: 'Provisional', unset: 'Unset',
+  da: 'DA', execution: 'Execution', state: 'State', networking: 'Networking',
 };
 
 export function Tag({ tag }: { tag: string }) {
diff --git a/app/scaling/components/firstScreen.test.tsx b/app/scaling/components/firstScreen.test.tsx
index b7419e8..5f95aa2 100644
--- a/app/scaling/components/firstScreen.test.tsx
+++ b/app/scaling/components/firstScreen.test.tsx
@@ -6,6 +6,7 @@ import { describe, expect, it } from 'vitest';
 import type { Snapshot } from '../snapshot.mjs';
 import { CeilingCards } from './CeilingCards';
 import { Guardrails } from './Guardrails';
+import { Progress } from './Progress';
 
 // Synthetic data only: real snapshots are internal and never committed.
 function fixture(): Snapshot {
@@ -48,3 +49,22 @@ describe('Guardrails', () => {
     expect(rows[3]).not.toMatch(/bg-bds-(green|red)/);
   });
 });
+
+describe('Progress', () => {
+  it('shows Linear state and a labelled bar when linked, and proposed with no bar otherwise', () => {
+    const [linked, proposed] = renderToStaticMarkup(<Progress work={fixture().work} />).split('px-4 py-3').slice(1);
+    expect(linked).toContain('>started<');
+    expect(linked).toContain('aria-label="4 of 10 issues done"');
+    expect(linked).toContain('width:40%');
+    expect(linked).toContain('Realized:');
+    expect(linked).toContain('href="https://example.com/synthetic/linear/project"');
+    expect(proposed).toContain('>proposed<');
+    expect(proposed).not.toContain('progressbar');
+    expect(proposed).not.toContain('Realized:');
+  });
+
+  it('hides realized without evidence', () => {
+    const [item] = fixture().work;
+    expect(renderToStaticMarkup(<Progress work={[{ ...item, evidence: null }]} />)).not.toContain('Realized:');
+  });
+});
diff --git a/app/scaling/page.test.tsx b/app/scaling/page.test.tsx
new file mode 100644
index 0000000..75068a7
--- /dev/null
+++ b/app/scaling/page.test.tsx
@@ -0,0 +1,14 @@
+import { fileURLToPath } from 'node:url';
+
+import { renderToStaticMarkup } from 'react-dom/server';
+import { expect, it, vi } from 'vitest';
+
+import ScalingPage from './page';
+
+it('collapses each detail section by default with its title and row count', async () => {
+  vi.stubEnv('SCALING_SNAPSHOT_PATH', fileURLToPath(new URL('./fixtures/synthetic.v2.json', import.meta.url)));
+  const html = renderToStaticMarkup(await ScalingPage());
+  expect(html).toMatch(/<details><summary[^>]*><h2[^>]*>Data availability<\/h2><span[^>]*> · 2 rows<\/span>/);
+  expect(html).not.toContain('<details open');
+  vi.unstubAllEnvs();
+});
diff --git a/app/scaling/page.tsx b/app/scaling/page.tsx
index cb7caf3..e12034c 100644
--- a/app/scaling/page.tsx
+++ b/app/scaling/page.tsx
@@ -9,7 +9,8 @@ import { Text } from '../components/ui/Text';
 import { CeilingCards } from './components/CeilingCards';
 import { Guardrails } from './components/Guardrails';
 import { Ladder } from './components/Ladder';
-import { isStale, parseSnapshot, type Metric, type Snapshot, type WorkItem } from './snapshot.mjs';
+import { Progress } from './components/Progress';
+import { isStale, parseSnapshot, type Metric, type Snapshot } from './snapshot.mjs';
 
 // The snapshot is a runtime file, so render per request rather than at build.
 export const dynamic = 'force-dynamic';
@@ -73,13 +74,16 @@ export default async function ScalingPage() {
       <CeilingCards ceilings={snapshot.ceilings} />
       <Guardrails guardrails={snapshot.guardrails} />
 
+      <Progress work={snapshot.work} />
+
       {snapshot.sections.map((section) => (
-        <section key={section.id} className="flex flex-col gap-3">
-          <div>
-            <Text as="h2" variant="headline">{section.title}</Text>
-            <Text variant="label.regular" tone="muted">{section.summary}</Text>
-          </div>
-          <Card className="divide-y divide-bds-gray-10 bg-background dark:divide-white/10 dark:bg-white/5">
+        <details key={section.id}>
+          <summary className="cursor-pointer select-none">
+            <Text as="h2" variant="headline" className="inline">{section.title}</Text>
+            <Text as="span" variant="label.regular" tone="muted"> · {section.metrics.length} {section.metrics.length === 1 ? 'row' : 'rows'}</Text>
+            <Text as="span" variant="label.regular" tone="muted" className="block">{section.summary}</Text>
+          </summary>
+          <Card className="mt-3 divide-y divide-bds-gray-10 bg-background dark:divide-white/10 dark:bg-white/5">
             {section.metrics.map((m) => (
               <div key={m.label} className="flex flex-col gap-1 px-4 py-3">
                 <div className="flex flex-wrap items-baseline justify-between gap-x-4 gap-y-1">
@@ -91,27 +95,16 @@ export default async function ScalingPage() {
             ))}
           </Card>
           {section.gaps.length > 0 ? (
-            <div className="rounded-lg border border-dashed border-bds-gray-10 px-4 py-3 dark:border-white/10">
+            <div className="mt-3 rounded-lg border border-dashed border-bds-gray-10 px-4 py-3 dark:border-white/10">
               <Text variant="label" tone="muted">Missing evidence</Text>
               <ul className="mt-1 list-disc pl-5 text-[13px] text-bds-gray-60">
                 {section.gaps.map((gap) => <li key={gap}>{gap}</li>)}
               </ul>
             </div>
           ) : null}
-        </section>
+        </details>
       ))}
 
-      <section className="flex flex-col gap-3">
-        <Text as="h2" variant="headline">What we&apos;re working on</Text>
-        {snapshot.work.length === 0 ? (
-          <EmptyState description="No current work supplied for this snapshot." />
-        ) : (
-          <div className="grid grid-cols-1 gap-3 md:grid-cols-2">
-            {snapshot.work.map((w) => <WorkCard key={w.title} item={w} />)}
-          </div>
-        )}
-      </section>
-
       <Text variant="label.regular" tone="muted">
         Experiment results: <Link className="underline" href="/benchmark/run">Benchmarks</Link> ·{' '}
         <Link className="underline" href="/benchmark/load-tests">Load tests</Link>
@@ -160,28 +153,6 @@ function MetricDetails({ metric, snapshot }: { metric: Metric; snapshot: Snapsho
   );
 }
 
-function WorkCard({ item }: { item: WorkItem }) {
-  const rows = [
-    ['Hypothesis', item.hypothesis],
-    ['Change', item.change],
-    ['Expected impact', item.expected ?? 'Not estimated'],
-    ['Realized impact', item.realized ?? 'Not measured'],
-  ];
-  return (
-    <Card className="flex flex-col gap-2 bg-background p-4 text-[13px] dark:bg-white/5">
-      <Text variant="label">{item.title}</Text>
-      <Text variant="footnote" tone="muted">{item.status} · {item.owner ?? 'No owner assigned'}</Text>
-      {rows.map(([term, text]) => (
-        <p key={term}><span className="text-bds-gray-60">{term}:</span> {text}</p>
-      ))}
-      <div className="flex flex-wrap gap-3">
-        {item.evidence ? <ExternalLink link={item.evidence} /> : null}
-        {item.links.map((l) => <ExternalLink key={l.url} link={l} />)}
-      </div>
-    </Card>
-  );
-}
-
 function ExternalLink({ link }: { link: { label: string; url: string } }) {
   return (
     <a className="w-fit underline" href={link.url} target="_blank" rel="noreferrer">