Oh I forgot to answer a question above. Both the single player and co-op campaigns are saved independantly from one another, but your PEC (Personal Elite Creation, something other Tom Clancy games uses) achievements and unlocks carry over between both modes. Progress in co-op is also tracked between the co-op players. For example, if you host and play 2 missions together, the next time you co-op partner decides to host, he / she will be able to select missions up to the point that he / she got to when someone else was the host. a lot of co-op capable games won't let you do this, although their co-op is based off the single player whereas this is a totally dedicated campaign.