Shower walls can be very frustrating and hard to keep dry. One problem I see most often is having a window in the shower stall. It is not impossible to keep the water out of the wall but is very difficult. When you consider that amount of moisture around the window it is not surprising. Here are some things I have tried in the past. The easiest thing to do is to put a large vinyl shower curtain over the window. Even this is not enough but it might surprise you how many people don’t even do this. Another thing I have done is to run a thin coat of silicon all over the window ledge and trim where water may leak in. If you are careful and use clear silicon it is not noticeable. Changing the type of shower head to a straight down water fall type may spare the window some as well.