How many campaign missions are there?

There are over 40 missions in the 1985 Campaign. Here's a list of them all:

1. Training
2. Flashpoint
3. Combined Arms
4. Camping
5. Alert
6. Montignac Must Fall
7. After Montignac
8. Strange Meeting
9. Rescue
10. Undercover
11. Night Patrol
12. Hold Malden
13. Defender
14. Tank Training
15. Battle at Houdan
16. Interdiction
17. Spearhead
18. Pathfinder
19. Tank Rally
20. Unfinished Business
21. Taking Command
22. Scouting
23. Turning the Tide
24. Sabotuer
25. Guardian
26. Return to Eden
27. Hind Attack
28. Rolling Thunder
29. Airborne
30. Air Superiority
31. Recon
32. Killdozer
33. Air Assault
34. Wake Up Call
35. Planes Start
36. Maverick
37. Counter Strike
38. Escaping From Prison
39. Incursion
40. Search And Destroy
41. Red Dawn
42. Status Quo

Some of these missions are bonus missions for a job well done. If your campaign book doesn't show one of the missions mentioned above, you might want to consider reverting back to the mission before the skipped mission and play it again in the hopes of earning a higher score and a chance to play the bonus mission.