The main mode of political, social and economic organisation of the interstellar age are communal systems. Three main elements constitute the political landscape of human space: Communes, Cooperatives and Qiths.

1 — Communes

Communes in their broadest definition refer to democratic social-political structures founded on shared principles. Communes may vastly vary in size and scope, from the superpowers that are the Moon Communes or the Giants' Collective to small station-based communes with a few thousand individuals.

Communes are the children of the Low Age and its radical redefinition of industrial-era politics and economics. While there are almost as many communal systems as there are communes, they all follow a set of principles that form the core of human society in the 26th century.

• Egalitarianism: all Communes strive to be as egalitarian as possible, especially in terms of individual wealth. Property in human space is neatly divided between what is considered as individual property — assets that do not produce wealth and whose ownership is not restricted — and private property — assets that do produce wealth. The restriction of the former to public ownership is one of the main tools to ensure economic equality inside a commune. From this shared economic basis, communes apply different degrees of enforced equality depending on their political alignment, from the complete quasi-communist uniformity of the USRE to the sprawling diversity of Eloran qiths. All communes, however, are virtually classless.
  
• Shared decision-making: communes try to maximize decision-making via consensus when it comes to commune-owned assets and properties. However, a fair share of communes have grown beyond the size where consensus is practical to implement and have installed democratic systems more reminiscent of late industrial-era direct democracies.
  
• Non-hierarchical structures: most small communes do not have hierarchies at all and implement a completely flat structure. Much like government via consensus, this system does not scale very well and elected hierarchies do exist in bigger communes, although they are always temporary and fleeting. The very structure of communes makes entrenchment of power unlikely and industrial-era political dynasties are mostly unknown.
  
• Common principles: not all communes were formed around shared principles (cooperatives, typically, are formed around an economic activity), but all of those that endured the test of time did at one point agree on a common ideological ground that creates the cement between a commune's members. These principles can vary from entire socio-political projects to looser principles, and even sometimes religious or spiritual beliefs. 

2 — Cooperatives

In the first decades of space settlement, all communes were also cooperatives, that is to say economic organisations owned and managed by their workers. As communes expanded and became the main mode of government in settled space, this paradigm changed. Many communes decided to stop coalescing around a simple economic service or activity to become a more comprehensive entity. Furthermore, the rise of truly massive communes with several million members created the risk of cooperatives starting to operate hierarchically once again, mirroring pre-Low Age corporations. The response to this state of things was the multiplication of smaller communes with streamlined institutions, focused solely on an economic goal. These cooperatives would often operate under the umbrella of a commune.

In very concrete terms, cooperatives are the main building blocks of interstellar economies, to the point top-down, non-cooperative companies only exist in fringe cases, mostly as tightly controlled weapons manufacturers. In the solar system, where communes tend to be massive structures entrenched in their political niches, cooperatives are the main vector of local democracy.

3 — Qiths

Qith is a neologism — though no one is certain where the word actually comes from. The concept was invented by Eloran settlers and covers the democratic institutions that constitute the building blocks of the Eloran polity. Qiths are not nations or countries, as they are not divided between territories but between different domains of activity and economic roles. They are not exactly castes, either, as qith membership is democratic and voluntary. They are always centred around a strong identity that blends economic, social, political and religious elements, to the point qiths can be understood as small societies that collaborate to create a vast federation of cooperative elements.

The main qiths are qith Saïmour (manufacturing, shipbuilding), qith Masani (agriculture, settlement), qith Sahaak (warfare, law enforcement), qith Hoyle (shipbuilding), qith Al-Aqsa (terraforming, environmental management) and qith Miramar (bureaucracy, administration).

Illustration from Steven Sander's Symbiosis Creative Commons artbook, licensed under a Creative Commons Attribution Non-Commercial Share-alike 3.0 unported license.