Hi anon, Wow, good question. This is a very broad topic and may not be possible to full answer in the confines of a forum. I'll highlight some key points which I also incorporate into retirement planning for my clients here, and hope that gives you something to work on. - You need to understand what kind of retirement lifestyle you want. Having a grasp of your expenses helps - You need to know what expenses are needs, and which are wants - You need to ensure that you have multiple streams of income, some of which must be guaranteed to meet your needs and some of which are variable to let you indulge in your wants - The more guaranteed income, the more peace of mind you have - With Excel, you will want to balance your cashflow over the years against your income stream over the years, factoring in inflation, etc. In the end, since no one knows how long you will live, instead of having a 'net worth number' to work towards, have a 'income stream' number instead.