White Space is the areas of your design that does not carry text, images or elements of communication. The white space is as important to your design as the content. Effective use will draw the attention of the reader or user to the most important content. Using too little white space will make the page or screen look over crowded and confusing. Too much white space will make the design seem sparse and ineffective. Balance is the key here.
Take a look at the new Sharefaith Newsletter Templates to get a good gauge on how much is enough when it comes to white space.