In broad terms, the CEO typically does fundraising and marketing. Realistically, both people will be working on many aspects of the business -- it's not always

In broad terms, the CEO typically does fundraising and marketing. Realistically, both people will be working on many aspects of the business -- it's not always prudent to silo duties early in a business. Based on other replies, equity and control may be issues that concern you. Spolsky's post on this matter is widely cited as a response to this question. There are also quite a few posts that dispute his thesis. These are relatively easy to google. This is one example: https://news.ycombinator.com/item?id=2493356 https://news.ycombinator.com/item?id=2493356 Here is a list: https://news.ycombinator.com/item?id=4941933 https://news.ycombinator.com/item?id=4941933 Note that there can be issues that 50/50 doesn't appear cover cleanly -- supplying cash, full time versus part time, building, selling, contacts/network, etc. Some would say that all of these other things, if they lead to something other than 50/50, may suggest the business is doomed from the start. While I will remain neutral on that question in this reply, it's certainly a good thought exercise. Most of all, I wonder if you would choose to marry your potential cofounder. If your response is not "hell yeah!", you may want to reconsider. You will effectively be married to this person for quite a while, and any weaknesses in your relationship will be amplified. Best of luck! (Edit: answered the original question)