As far as structure goes you just have talk it out with those involved and find out what everyone is comfortable with. Obviously this can be a great challenge and at other times it is so simple it is mind boggling. As far as the ebb and flow of relationships through the network... umm ... well some times it just happens on it's own and some times you have to do some soul searching and personal analysis. Once again it is up to the individuals involved and just talking it out. The thing that makes polyamory work for me is the level of freedom and the diversity of love, experiences, and relationship interactions I have. Also, there are desires and needs that some people can and will fulfill, won't or cant fulfill, or a mix of both. So I get those needs met or help meet the needs with and for my other partners. As far as keeping everyone feeling connected, you now get in to the whole "primary/secondary" thing. Many people have a lot of varied opinion on that subject but basically it comes down to the fact that it is very difficult to be "primaries" with all your partners. A lot of times the resources just aren't there; time, money, energy, ect. Most poly networks have different and varied levels of involvement between the multiple partners. Once again lots of open honest communication is necessary. Any relationship obviously requires good communication skills but, when you add more people to a situation the greater the demand becomes for good communication.