async function handleAccessRequest(userId, email) {
  // Verify identity
  const verified = await verifyIdentity(email);
  if (!verified) throw new Error('Identity verification failed');

  // Collect all personal data
  const userData = await collectUserData(userId);

  // Format for readability
  const report = {
    personalInfo: userData.profile,
    activityLogs: userData.activities,
    preferences: userData.settings,
    thirdPartySharing: userData.dataSharing,
    retentionPeriod: '2 years from last activity',
    dataProtectionOfficer: 'dpo@company.com'
  };

  // Generate downloadable report
  const pdf = await generatePDFReport(report);

  // Log request for compliance
  await logAccessRequest(userId, 'completed');

  return pdf;
}

async function handleDeletionRequest(userId, email) {
  // Verify identity
  const verified = await verifyIdentity(email);
  if (!verified) throw new Error('Identity verification failed');

  // Check for legal obligations to retain
  const mustRetain = await checkRetentionRequirements(userId);
  if (mustRetain.required) {
    return {
      status: 'partial_deletion',
      retained: mustRetain.data,
      reason: mustRetain.legalBasis,
      retentionPeriod: mustRetain.period
    };
  }

  // Delete from all systems
  await Promise.all([
    deleteFromDatabase(userId),
    deleteFromBackups(userId), // Mark for deletion in next backup cycle
    deleteFromAnalytics(userId),
    deleteFromThirdPartyServices(userId),
    revokeAPIKeys(userId),
    anonymizeHistoricalRecords(userId)
  ]);

  // Confirm deletion
  await sendDeletionConfirmation(email);
  await logDeletionRequest(userId, 'completed');

  return { status: 'deleted', timestamp: new Date() };
}

async function handlePortabilityRequest(userId, format = 'json') {
  const userData = await collectUserData(userId);

  // Structure in machine-readable format
  const portableData = {
    exportDate: new Date().toISOString(),
    userId: userId,
    data: {
      profile: userData.profile,
      content: userData.userGeneratedContent,
      settings: userData.preferences,
      history: userData.activityHistory
    }
  };

  // Support multiple formats
  if (format === 'csv') {
    return convertToCSV(portableData);
  } else if (format === 'xml') {
    return convertToXML(portableData);
  }

  return portableData; // JSON by default
}

async function handleObjectionRequest(userId, processingType) {
  switch (processingType) {
    case 'direct_marketing':
      // Must stop immediately
      await disableMarketing(userId);
      await updateConsent(userId, 'marketing', false);
      break;

    case 'legitimate_interest':
      // Assess if we have compelling grounds
      const assessment = await assessLegitimateInterest(userId);
      if (!assessment.compelling) {
        await stopProcessing(userId, processingType);
      }
      return assessment;

    case 'profiling':
      await disableProfiling(userId);
      await updateConsent(userId, 'profiling', false);
      break;

    default:
      throw new Error('Invalid processing type');
  }

  await logObjectionRequest(userId, processingType, 'granted');
}

<!-- Good: Granular consent -->
<form>
  <h3>Privacy Preferences</h3>

  <label>
    <input type="checkbox" name="essential" checked disabled>
    <strong>Essential cookies (Required)</strong>
    <p>Necessary for website functionality</p>
  </label>

  <label>
    <input type="checkbox" name="analytics" value="analytics">
    <strong>Analytics cookies</strong>
    <p>Help us improve our website by collecting usage data</p>
  </label>

  <label>
    <input type="checkbox" name="marketing" value="marketing">
    <strong>Marketing cookies</strong>
    <p>Show you personalized ads based on your interests</p>
  </label>

  <button type="submit">Save Preferences</button>
  <a href="/privacy-policy">Learn More</a>
</form>

const consentRecord = {
  userId: 'user123',
  timestamp: new Date().toISOString(),
  consentVersion: '2.0',
  purposes: {
    essential: { granted: true, required: true },
    analytics: { granted: true, purpose: 'Website improvement' },
    marketing: { granted: false, purpose: 'Personalized advertising' }
  },
  ipAddress: '192.168.1.1', // For proof
  userAgent: 'Mozilla/5.0...', // For context
  method: 'explicit_opt_in' // or 'implicit', 'presumed'
};

await saveConsentRecord(consentRecord);

<div id="cookie-banner" role="dialog" aria-labelledby="cookie-title">
  <h2 id="cookie-title">Cookie Preferences</h2>
  <p>
    We use cookies to enhance your experience. Choose which cookies you
    allow us to use. You can change your preferences at any time.
  </p>

  <button onclick="acceptAll()">Accept All</button>
  <button onclick="rejectNonEssential()">Reject Non-Essential</button>
  <button onclick="showPreferences()">Manage Preferences</button>
</div>

<script>
// Must not load non-essential cookies until consent given
function acceptAll() {
  setConsent({ analytics: true, marketing: true });
  loadAnalyticsCookies();
  loadMarketingCookies();
  hideBanner();
}

function rejectNonEssential() {
  setConsent({ analytics: false, marketing: false });
  hideBanner();
}
</script>

// ❌ Bad: Collecting unnecessary data
const userRegistration = {
  email: req.body.email,
  password: req.body.password,
  fullName: req.body.fullName,
  phoneNumber: req.body.phoneNumber, // Not needed
  dateOfBirth: req.body.dateOfBirth, // Not needed
  address: req.body.address, // Not needed
  socialSecurityNumber: req.body.ssn // Definitely not needed!
};

// ✅ Good: Only essential data
const userRegistration = {
  email: req.body.email,
  password: hashPassword(req.body.password),
  displayName: req.body.displayName // Optional
};

// Document and enforce purpose
const dataProcessingPurpose = {
  email: [
    'account_authentication',
    'order_confirmations',
    'password_reset'
  ],
  phoneNumber: [
    'order_delivery_notifications'
    // NOT: 'marketing_calls' (requires separate consent)
  ],
  purchaseHistory: [
    'order_fulfillment',
    'customer_support'
    // NOT: 'targeted_advertising' (requires separate consent)
  ]
};

async function processData(data, purpose) {
  if (!isAllowedPurpose(data.type, purpose)) {
    throw new Error('Purpose not authorized for this data');
  }
  // Proceed with processing
}

const retentionPolicy = {
  userAccounts: {
    active: 'indefinite',
    inactive: '2 years',
    deleted: '30 days grace period'
  },
  orderRecords: '7 years', // Legal requirement
  supportTickets: '3 years',
  analytics: '26 months',
  marketingData: '1 year or until consent withdrawn'
};

// Automated data deletion
async function enforceRetentionPolicy() {
  const now = new Date();

  // Delete inactive accounts
  await User.deleteMany({
    lastActive: { $lt: subYears(now, 2) },
    status: 'inactive'
  });

  // Anonymize old analytics
  await Analytics.updateMany(
    { createdAt: { $lt: subMonths(now, 26) } },
    { $unset: { userId: 1, ipAddress: 1 } }
  );

  // Delete expired marketing consent
  await MarketingConsent.deleteMany({
    $or: [
      { expiresAt: { $lt: now } },
      { withdrawnAt: { $lt: subDays(now, 30) } }
    ]
  });
}

// Schedule daily
cron.schedule('0 2 * * *', enforceRetentionPolicy);

# Data Protection Impact Assessment

## Processing Overview
- **Purpose**: [Describe the processing activity]
- **Data Types**: [Personal data categories]
- **Data Subjects**: [Who is affected]
- **Recipients**: [Who receives the data]

## Necessity Assessment
- [ ] Is processing necessary for the stated purpose?
- [ ] Could the purpose be achieved with less data?
- [ ] Is the retention period justified?

## Risk Assessment
| Risk | Likelihood | Severity | Mitigation |
|------|------------|----------|------------|
| Data breach | Medium | High | Encryption, access controls |
| Unauthorized access | Low | High | 2FA, audit logs |
| Purpose creep | Medium | Medium | Purpose documentation, training |

## Safeguards
- [ ] Encryption at rest and in transit
- [ ] Access controls and authentication
- [ ] Regular security audits
- [ ] Data minimization applied
- [ ] Retention policies enforced
- [ ] DPO consulted
- [ ] Data subject rights mechanism in place

## Conclusion
Processing is/is not acceptable with proposed safeguards.

Signed: [Data Protection Officer]
Date: [Assessment Date]

# Privacy Policy

## 1. Identity of Controller
Company Name, Address, Contact Information
Data Protection Officer: dpo@company.com

## 2. Data We Collect
- Account data: email, name
- Usage data: pages visited, features used
- Technical data: IP address, browser type

## 3. Legal Basis for Processing
- **Consent**: Marketing communications
- **Contract**: Order fulfillment
- **Legitimate Interest**: Fraud prevention
- **Legal Obligation**: Tax records

## 4. How We Use Your Data
- Provide services you requested
- Improve our products
- Send important updates
- [Be specific, avoid vague statements]

## 5. Data Sharing
- Payment processors (Stripe, PayPal)
- Shipping providers (FedEx, UPS)
- Analytics (Google Analytics)

We do NOT sell your personal data.

## 6. Your Rights
- Right to access your data
- Right to correct inaccuracies
- Right to delete your data
- Right to object to processing
- Right to data portability
- Right to withdraw consent

Contact: privacy@company.com

## 7. Data Retention
- Account data: Until account deletion + 30 days
- Order history: 7 years (legal requirement)
- Marketing data: 1 year or until opt-out

## 8. Security
We use industry-standard security measures including
encryption, secure servers, and regular security audits.

## 9. International Transfers
Data may be transferred to US servers. We use Standard
Contractual Clauses approved by the EU Commission.

## 10. Changes to Policy
Last updated: [Date]
We will notify you of material changes via email.

## 11. Contact
Questions? Contact our Data Protection Officer at dpo@company.com

1. **Detect & Contain** (0-4 hours)
   - Identify scope of breach
   - Isolate affected systems
   - Prevent further data loss

2. **Assess** (4-24 hours)
   - Determine data types affected
   - Identify number of individuals
   - Assess risk to rights and freedoms
   - Document everything

3. **Notify Authority** (24-72 hours)
   - Report to supervisory authority
   - Include: nature, categories, approximate numbers,
     likely consequences, measures taken

4. **Notify Data Subjects** (ASAP if high risk)
   - Direct communication required
   - Describe breach in clear language
   - Provide recommendations for protection

Subject: Important Security Notice

Dear [Name],

We are writing to inform you of a data security incident that may
have affected your personal information.

WHAT HAPPENED:
On [date], we discovered that [brief description].

WHAT INFORMATION WAS INVOLVED:
[List specific data types: name, email, etc.]
[List what was NOT involved]

WHAT WE ARE DOING:
- [Immediate actions taken]
- [Ongoing security enhancements]
- [Resources provided to affected individuals]

WHAT YOU CAN DO:
- Change your password immediately
- Monitor your accounts for suspicious activity
- [Specific recommendations]

FOR MORE INFORMATION:
Contact our dedicated hotline: [phone]
Email: security@company.com

We sincerely apologize for this incident and the inconvenience
it may cause.

Sincerely,
[Name, Title]