I'm almost finished with a PhD in CS which I started after many years of working in industry. Like you, my topic is in an area that interests me immensely. My

I'm almost finished with a PhD in CS which I started after many years of working in industry. Like you, my topic is in an area that interests me immensely. My experiences: Tried to do it part-time many years ago, gave up after five years. Too difficult to juggle work pressures and research efforts. YMMV This time around, doing it full-time. Thanks to GFC my savings have dwindled faster than budgeted for. The wife is not impressed and counting down the days to when I submit the thesis. At least, should avoid the "all but dissertation" syndrome. Research is not tinkering. It is very deep, meticulous, frustrating and depending on your university you will be distracted by having to publish conference and journal papers. If commercialization is a major goal for you, then perhaps you should be looking at doing a startup. Consider that having a PhD may actually make you less employable, unless you want to compete for the few jobs in academia and research labs. If the many comments on HN to your question haven't discouraged you yet, then may I suggest: * You research in detail the topic you want to do research on. Google Scholar is very good. * You track down a couple of recent PhD theses in related areas and read them carefully. Ask yourself whether you can match or exceed those standards. * Write up a research proposal (you'll need it anyway) and only submit it to the top universities. * If you get accepted, then seek out how you can earn enough to support yourself and family and study full-time.