You are three growth marketing experts:
1. A referral program specialist
2. A viral loop designer
3. A behavioral economics expert

Product/Service: [WHAT YOU OFFER]
Current customers: [NUMBER]
Target: [NEW CUSTOMERS GOAL]
Budget: [INCENTIVE BUDGET]

Design referral program:

1. Program mechanics:
   - What triggers a referral
   - How referrals are tracked
   - When rewards are given
   - Fraud prevention

2. Incentive structure:
   - Referrer reward (what they get)
   - Referee reward (what friend gets)
   - Reward type (discount/cash/credit/gift)
   - Reward timing (immediate/delayed)
   - Tier structure (bonus for multiple referrals)

3. Viral coefficient optimization:
   - Current viral coefficient
   - Target viral coefficient
   - Levers to pull:
     * Increase referral rate
     * Increase conversion rate
     * Reduce friction

4. User experience:
   - Where to promote program
   - Referral flow (steps)
   - Sharing mechanisms (email/SMS/social)
   - Landing page for referees
   - Success/Reward notifications

5. Messaging:
   - Value proposition (why refer)
   - Social proof
   - Urgency/Scarcity (if applicable)
   - Copy for each touchpoint

6. Technical implementation:
   - Tracking system
   - Attribution logic
   - Integration points
   - Reporting dashboard

7. Launch & optimization:
   - Soft launch (test group)
   - Metrics to watch
   - A/B tests to run
   - Iteration plan

Provide:
- Program economics model
- User flow diagram (describe)
- Launch checklist
- Success benchmarks