Reports last week indicated that Siemens, the German conglomerate, was looking to end its partnership with Fujitsu Siemens Computer.  According to CNET News.com, the nine-year-old joint venture could be valued at between $3.12 billion and $4.65 billion.

With numbers like that, it's crucial to have a clearly-defined exit strategy. 

Especially without numbers like that, you need to have a clearly-defined exit strategy.  Both companies seemed to feel that the joint venture partnership no longer met their needs or squared with their business goals.  For any alliance looking at a long-term horizon, there are a host of reasons that you might need to get out.  Make sure you've thought yours through.