One sign that the economy is improving is that there are more mergers happening, as companies free up cash to invest in other ongoing businesses. Having seen a few of these firsthand, I offer ten suggestions on how things can go wrong, and what IT managers and CIOs should look out for. And yes, if you know my work history, you can figure out which mergers I draw on here.

1. Ignore employee contracts. At announcement day you should have a plan in place over who stays and who goes, and plan on honoring longer-term contracts, even paying bonuses when called for. The good people – especially your key developers and technical staff — aren’t going to be watching what happens to their contracts. Mess with this, and they won’t stick around a minute more than they have to.

2. Speaking of which, give everyone meager bonuses upon the merger announcement. Some people are getting big payouts, but try to fair with those that aren’t owners.

3. Overpromise when changes will be implemented. If everything is going to happen “within 90 days” after the acquisition, make it so. Like never-ending software projects, this could turn into a moving time window and these changes never get implemented. Better yet, figure out what you can do within two weeks’ time, and focus on these short-term objectives.

4. Have no clear chain of command in the new regime. Who approves travel requests? Where does someone call when someone’s invoice doesn’t get paid? What are the new regulations for cell phone reimbursement? Who approves new hosting contracts or software purchases? This nitty-gritty stuff can be easy or hard, depending on the marriage of corporate cultures and policies. Pay attention to this stuff before the announcement.

5. Take your sweet time to define new roles. This should be part of the acquisition plan. The longer you delay this, the quicker people will start leaving out of frustration over the ambiguity. This is especially the case for IT departments that have overlapping responsibilities.

6. Treat your developers like commodities. Regardless of whether you want to keep them or not, you will need them to help with the transition to whatever systems the new overlords have. A bad sign is when developers leave soon after the merger, showing they don’t have much confidence in the combined company.

7. Pay your contractors slowly. If you don’t have procedures in place to absorb new contractors and get them paid, they will find other clients quickly. Figure out how many independent contractors are on board in the acquired company and make them happy by getting your HR systems in place to pay them as quickly as possible under the new regime.

8. Keep the announcement a secret from the staff. I’ve seen mergers where the first anyone hears about it is in the press. That isn’t a good strategy. Your staff knows that something is up, so trust them to keep it quiet. By not doing so you set the wrong tone for what should be a very exciting day. At least let your managers know what is going on ahead of time.

9. Insist that everyone immediately relocate to the new HQ. Come on, this is 2012! Accept that people will want to work from wherever they currently live, and invest in hiring managers who are comfortable with supervising remote workers. Make sure you have the technology in place to encourage distributed work teams too. Let the moving evolve slowly as individuals need to find their new niche in an organization. One of my favorite positions was long ago at PC Week (now called eWeek). I started out working remotely for them, me in Los Angeles and they in Boston. Over time I got promoted and it became obvious that I needed to be in the Mother Ship. But it was a joint decision, not something dictated by HR fiat. When you let things evolve, it goes a long way towards improving morale and keeping the key people on your team.

10. Spend lots on window dressing. One firm that I knew spent lots of money on a new domain name, leaving little in the budget for other, more substantial items. A domain name isn’t any good without the associated content and the people to contribute value.

These are by no means the only ten mistakes that I have seen over the years. What were your favorite merger blunders?