There are several major models of polyamory that involve varying levels of privilege and responsibility between the various people in relationship together. One of the ways we see this expressed is in hierarchical language, like primary, secondary and tertiary. This tends to denote how the practical application of connection works, but there are a lot of people that don't like this language, finding it demeaning or limiting.
I'm looking at trying a different model of how to relate based on the degree that a person wants to be responsible to others, as well as the privileges they might have a reasonable expectation of having access to: Island, peninsula or continent.
An "island" person would be someone who prefers strongly to be very independent. They don't want to run decisions past others, participate in consensus within a group, be "on call" to anothers' emotional or physical needs, and might see those levels of entanglement to be co-dependent or undesirable. Relationships are loosely defined, if at all, although they tend to have intense emotions surrounding relationships. Giving and receiving are seen as independent choices with no strings attached to islands.
A "peninsula" person still values their independence highly, but sees value in having some connection on an on-going basis with others. They will participate in consensus, but may still go their own way at any time. Give a little, get a little, but seldom at expense of their own goals or objectives. Connections may be strong, but are often less entwined in daily living. Giving and receiving usually run pretty quid pro quot, with a balance being sought.
A "continent" type looks to build strong tensile strength in their networks. Consensus is highly important, to the point that some of their own desires and needs can be sublimated for the health of the group. The deep level of commitment to their relationships may cause them to appear to be dependent on their partners at times. They value responsibility, and have a tendency to over-give. Giving and receiving are important parts of why they are in relationships with others, and connections feel less significant if there isn't a level of responsibility attached.
How do these (admittedly highly general approaches!) work in application? One possibility- Let's say you have a "island" dating a "continent": The continent is looking for a level of connection involving responsibility and intimacy that the island is likely to find stifling, and may feel rebuffed when their requests for help are declined. The island may be confused as to why their personal decisions are questioned, or that their partner wants them to participate more fully within daily life. In this case it may be helpful to find someone who knows how to build bridges, or have each partner move more closely toward a peninsula mindset.
Would it be helpful to understand the general approaches that a potential partner has on independence, entanglement, responsibility and privileges before starting a relationship? Of course! Even after the fact, it can be very useful to "retrofit" a relationship to allow more flexibility between styles, as well as just understand when someone has a totally different take on the word "relationship" than you do.
One thing that can be very challenging is when rights and privileges are desired without the accompanying responsibilities or vice versa. This can look a little like S's 11 year old saying she wants a cell phone. Alas, she doesn't have a job, has no way to pay for that item, as well as monthly upkeep on it. In the same way, someone that doesn't put into the relationship "bank" may find themselves short when the time comes that they want to make a withdrawal. Whereas, someone who gives to a person that doesn't record their deposits will be shocked to find that there is no running balance when they need to pay an unexpected bill.
FYI: I'm a continent with peninsula leanings. How about you? ;)