Flow is a concept introduced by Mihaly Csikszentmihalyi; in short, it means to get into the "zone". You feel immersed in your task, focused; the task can be difficult but challenging at the same time. When people achieve flow their productivity shoots up. Programming requires a great deal of mental focus because we often need to juggle several things in our minds at once. Many like to work in a quiet environment where they can direct their full attention to the task. If they are interrupted, it may take several minutes or even hours to get back into flow.
I understand there's a practice in agile development and extreme programming called pair programming. It means you put the whole software development team in one room so that communication is seamless. You do write code with your pair because this way you get instant code reviews and fewer bugs get through.
I've always had problems achieving flow while doing pair programming because of constant interruptions. I'm thinking deep about an issue then all of sudden someone asks me a question from another pair. My train of thought is lost.
How can you achieve and maintain flow while pair programming?