protecting references from overload

A reader writes:

I am always on a job prowl and, thus, in need of references. I read that it's good to give references the job descriptions and updates so they can be prepared to give a good reference. However, as I am doing a wide sweeping job search, I am reluctant to email them time and time again. Should I email them a general email listing the types of jobs I might be looking for? Or, should I update them more about the actual positions so they won't be surprised over the next two months? I tried maintaining good communication with them by emailing them, asking about updates on what they're doing and offering to help in projects related to ones I have worked on before. Yet, from their responses, I know most of them are really very busy.

Actually, there's a very easy answer to this: Don't provide prospective employers with your references until you're in the final stages of interviewing for a job. Most employers aren't going to check references until they're seriously considering making you an offer anyway (it's time-consuming and there's no point until you're seriously considering hiring someone). In fact, wait until the employer specifically asks you for your references -- at that point and only at that point, provide them and give your references a heads-up, with details about the nature of the job.

And if an employer asks you for your references at the very outset of the process, it's completely fine to request that they not be contacted until the employer is seriously interested in making you an offer (and that you be notified first so that you can alert them).