Let's say you and a potential guest both want the interview to happen, but you just cannot work out a time when you are both available. A method a few podcasters use to get around this problem is to conduct what's called a time-shifted interview.
We recommend that you have the interviewee read the questions out loud before answering each one. Not only does this help you keep track of where he or she is in the list of questions, but it can also make that person sound more natural when answering.
How this works is simple: You send an email to the guest with some questions. The guest then records his or her responses to the questions and sends you the recording.
You then record the questions and mix together the two. You can even do follow-up questions this way. Like a double-ender, this method is pretty much limited to those who are comfortable doing a recording on their end and have the time and desire to put it together and send it to you. This is not something you would be asking Paris Hilton to do for your show. Another downside to this method is that there is no real interaction with the guest and no chance to bond. Most interviews done this way have a clear lack of chemistry between the guest and the host.