An IPO is one of the highlights in the history of a company. This thesis talks about one of the most important decisions at the time of the IPO: which investment bank should we choose? First of all, an analyses is given of the pros and cons of an IPO and why a company should work with an investment bank. The next chapter talks about characteristics that might influence this decision. Afterwards, an empirical study on 50 Belgian IPOs is performed to test the validity of the characteristics and the actual influence they have on the decision.