One of the major causes of divorce is financial problems, so you can see why this question is important. If you just recently got married or are thinking of getting married then you should consider looking at how the money will be managed in the relationship.
The most important thing is communication and both being on the same page. Goals should be established early on such as what bills need to be paid, budget for food and gas as well as short and long term savings. If you each have different goals and on two different pages then there will obviously be disagreements with what to do with the money. This will lead to arguing and an unhealthy relationship. Spend some time right away to identify goals and needs.
First, identify who will manage the money. This can be one or both of you. If one gets easily stressed out with budgeting and doesn't want to deal with it or listen that's fine but should let the other manage it and not get upset when money is not available for unnecessary spending otherwise they should become involved by sitting down and going over at least a general plan.
If there is still uncertainty about managing money and what goals each person has then one option is to separate funds at first with a shared account for common bills. Agree on what bills each of you is responsible for and what bills will be shared. Identify if it will be a 50/50 sharing of bills or another ratio from the very beginning. This way you will each have control of your own funds to do as you wish while equally contributing to shared expenses. This can be permanent or temporary until you develop a good system and decide to work together.