Part I. The Background: 1. Introduction; 2. Inside the atom; 3. Quarks and leptons; 4. Unification of forces; Part II. The Objective: 5. The experimental test; 6. How do we recognise a W or Z boson?; Part III. The Tools for the Search: 7. Accelerators and CERN; 8. Detectors; 9. The UA1 experiment; Part IV. The Search: 10. Installation and the early runs; 11. The search for the W boson; 12. The search for the Z boson; 13. The search continues; Part V. The Future: 14. What next?; Appendix.