Question: My company has recently acquired another small company. Now, my company has a ERP system that we are using it presently. Also, the acquired company has an ERP system of its own. 

Now I have been given the responsibility of integrating my company's ERP System with the ERP system of the recently acquired company. To do this, I have to map the data between these two processes and see if there are any redundant features. 

However I was told by my friends that there would be lot of problems when I need to sit with both employees of the two companies, given the fact that my company doesn't treat the other company employees that well in terms of credibility. 

So I wanted to know, how do I make sure that there are no hard feelings between both sets of employees and what steps do I take for effective brainstorming sessions among both the teams?

Answer: 
* Don't let your plans or meetings be tainted by what other people have said re the feelings each side has.
* Prepare for different situations but leave the preconceived notions behind.
* Go in with an open mind and make your own, independent assessment of the potential challenges and opportunities.
Bring pizza or cookies to the kickoff/first meeting. Talk about the culture, the takeover, and other elephants in the room. Try to find common ground and common goals. If you can accomplish that in the first meeting you've accomplished a lot. 

If nothing else, tell them this will look good on your resume, too. Let them know you didn't personally commit the takeover, etc. In other words, you need to establish a trusted relationship before you can expect cooperation. It will take time - but people come around quickly in these situations, especially in bad economic times.
Good luck.