My short answer is fiction, in most cases. I think it totally depends on your unique situations, but I certainly wouldn't say there is NO way to make money for 6-12 months. I think if you're in a progression phase from a comfy, steady, easy corporate job to your own venture, you need to be strategic and play scenarios out in your head before taking the plunge. There'll be plenty of days where you just think to yourself "You're quitting tomorrow and we can figure out the income thing the day after" - Which is a natural thought process for an entrepreneur. Of course, taking action is a great but I personally believe in taking calculated massive action. For example, if part of your progression plan is to leverge existing business relationships - make sure you've planted some solid seeds with those people before just jumping out of your day job and losing your income. (You'll want to consider legal ramifications here too - It's often not a great idea to try and steal your previous employers' customers). Build systems for your new venture, get up at 4am daily and spend the first 5 hours of each day getting stuff done that will move you towards a smooth progression financially. And yes, I agree with the other respondents that it's definitely a great idea to have some savings set aside if possible, or at least some solid committed customers for your new venture.