cross that bridge when one comes to it

Fig. to delay worrying about something that might happen until it actually does happen. (Usually used in the phrase, "Let's cross that bridge when we come to it," a way of telling someone not to worry about something that has not happened yet. Alan: Where will we stop tonight? Jane: At the next town. Alan: What if all the hotels are full? Jane: Let's cross that bridge when we come to it.