"Headwork" is a slang term used in the online multiple community for self-improvement work that helps people deal with their issues and problems. Most people know about "self-improvement" literature, and abuse recovery books, etc. such as those that are found in libraries and bookstores under "Self-Help." Headwork is the work that happens when people are improving themselves. Everybody can tinker with their thoughts, feelings, emotions, reactions, etc. In the case of multiples, it can also be used for things like alteration of internal landscape, building mental constructs, and so on.
Headwork is particularly useful when discussing multiplicity because, in most cultures, does not come with healthy role-models, examples of intra-social interaction, helpful documentation, etc. Multiplicity itself may come with it's own issues and potential baggage, whether or not there was abuse in the system's past, simply by way of a lack of appropriate role models, feeling different, and uncertainty that you are normal or sane.
Not all multiples do headwork, and not everyone who does headwork is multiple. That is not a testimony to whether or not any particular individual or system needs it, and certainly doing headwork carries risks that may rival having not done it at all. That being said, there's enough precident that walking through life with your blinders on, in denial, living moment-to-moment is not particularly safe or fulfilling for singletons, and there's no reason that multiples are exempt from similar needs for self-actualization or enlightenment, or working on baggage and issues, imperfections or flaws, whether they developed in childhood or later on in life when their lover was manipulative towards them, when they witnessed a disaster like 9-11, or, as an example that no one is exempt from, a loved one dies. This makes an apt commonplace example for why multiplicity + headwork is it's own topic: People grieve, for example, at the loss of pets and loved ones, and there is a period of healing. In multiplicity, this is colored by having a closely knit group of people all with different memories and thoughts about that person, and the grief process can be more like an internal group mourning session, and there may be additional complications as one person reminds another of the bereaved. This is one case where being multiple can change the experience had by singletons as discrete entities, or more aptly brings group social dynamics into one individual head with the caveat that certain resources are limited, such as front-time.
Headwork is not at all a requirement of multiplicity, but at some point or other you're likely to discover that there's something about you -- whether system wide or for one individual within the system -- that the group or individual in question wants to change. This is a resource section for such "self-as-group" and "self-within-group" improvement.
Note that it is certainly by no means the sole purpose of this manual to put forth a methodology for headwork, and as we said before, headwork has consequences that may not be desirable. This section is written to discuss either theory, research, studies, or our own experiences, not as anything resembling professional advice.