Good family history researchers know that there is no habit more valuable than keeping a good research log. A research log helps you keep track of what sources you have searched, which individuals you searched for, the results of your searches, and when you conducted the said searches.

If you're like most of us, you squeeze genealogy in around all the other demands on your time. You may fit in a half hour of research here and there; sometimes you may put down a project not to take it up again until six months later. Six months from now, or even a week from now, you won't remember exactly which sources and which years you've searched. That is why a research log is so invaluable. Nothing is worse than wasting your time duplicating searches that you've already done just because you can't quite remember what you've searched already and what you haven't. But if you keep a good research log, you can take up a project after not working on it for months and pick up right where you left off.

How do you keep a good research log? It doesn't matter if you make an Excel spreadsheet or write it out with pen and paper. There are, however, a few elements that all good research logs have in common:

• The source you searched. Don't just put "1820 census"; it's too vague. Record the specifics of the source you searched, and what years you searched. For example: "Hardy County, West Virginia, Personal Property Tax Records, Years 1807 to 1819, on Family History Library US/Canada Microfilm 250005."

• What information you searched for. Did you search Orange County marriage records just looking for your grandmother's name? Or did you also look for the marriage record of her sister while you were searching? Did you search for your grandmother under her given name, Sarah? Or did you also search for Sally, which is a common nickname for Sarah? Keep track of these kinds of details so that in the future you'll know if you need to go back and search records again.

• Results. If you found what you were looking for, record it. If you didn't find what you were looking for, record that. Recording "nil" searches is just as important as recording the documents you did find, because doing so will save you from unnecessarily searching the same records again looking for ancestors that aren't there. If you do find what you're looking for, the best thing to do is to photocopy or print the document, label what it is and where it came from, and also label it with a document number. Then record that document number in your research log. Your research log can then serve as a table of contents for your documents.

• Date. It's important to keep track of when you performed searches. That way, if you make a momentous discovery about an ancestor - that he was married to a different woman than you originally thought, for instance-you can go back through your research logs and see which searches need to be re-done to take this new information into account.

Making a detailed research log may seem like a lot of work - and it is. But keeping a good log will save you a lot of hassle, and it will actually save you a lot of time in the end.