Physical resources are often organized according to intrinsic physical properties like their size, color, or shape, because the human visual system automatically pays a lot of attention to them.

This inescapable aspect of visual perception was first formalized by German psychologists starting a century ago as the Gestalt principles (see the sidebar, Gestalt Principles). Likewise, because people have limited attentional capacity, we ignore a lot of the ongoing complexity of visual (and auditory) stimulation, making us perceive our sensory world as simpler than it really is. Taken together, these two ideas explain why we automatically or “pre-attentively” organize separate things we see as groups or patterns based on their proximity and similarity. They also explain why arranging physical resources using these quickly perceived attributes can seem more aesthetic or satisfying than organizing them using properties that take more time to understand. Look at the cover of this book; the most organized arrangement of the colors and shapes just jumps out at you more than the others.

This simple example of a list of files illustrates the Gestalt similarity principle that elements that look similar are seen as being in the same group. The shape and visual design for the icons distinguishes files from folders, and file types from each other. These interpretations do not require you to be able to read the labels, although the visual similarity of the names suggests some similarity of content.

Physical resources are also commonly organized using intrinsically associated properties such as the place and time they were created or discovered. The shirts in your clothes closet might be arranged by color, by fabric, or style. We can view dress shirts, T-shirts, Hawaiian shirts and other styles as configurations of shirt properties that are so frequent and familiar that they have become linguistic and cultural categories. Other people might think about these same properties or categories differently, using a greater or lesser number of colors or ordering them differently, sorting the shirts by style first and then by color, or vice versa.

In addition to, or instead of, physical properties of your shirts, you might employ behavioral or usage-based properties to arrange them. You might separate your party and Hawaiian shirts from those you wear to the office. You might put the shirts you wear most often in the front of the closet so they are easy to locate. Unlike intrinsic properties of resources, which do not change, behavioral or usage-based properties are dynamic. You might move to Hawaii, where you can wear Hawaiian shirts to the office, or you could get tired of what were once your favorite shirts and stop wearing them as often as you used to.

Some arrangements of physical resources are constrained or precluded by resource properties that might cause problems for other resources or for their users. Hazardous or flammable materials should not be stored where they might spill or ignite; lions and antelopes should not share the same zoo habitat or the former will eat the latter; adult books and movies should not be kept in a library where children might accidentally find them; and people who are confrontational, passive aggressive, or arrogant do not make good team members when tough decisions need to be made. For almost any resource, it seems possible to imagine a combination with another resource that might have unfortunate consequences. We have no shortage of professional certifications, building codes, MPAA movie ratings, and other types of laws and regulations designed to keep us safe from potentially dangerous resources.

To overcome the inherent constraints with organizing physical resources, organizing systems often use additional physical resources that describe the primary physical ones, with the library card catalog being the classic example. A specific physical resource might be in a particular place, but multiple description resources for it can be in many different places at the same time.

When the description resources are themselves digital, as when a printed library card catalog is put online, the additional layer of abstraction created enables additional organizing possibilities that can ignore physical properties of resources and many of the details about how they are stored.

In organizing systems that use additional resources to identify or describe primary one’s “adding to a collection” is a logical act that need not require any actual movement, copying, or reorganization of the primary resources. This virtual addition allows the same resources to be part of many collections at the same time; the same book can be listed in many bibliographies, the same web page can be in many lists of web bookmarks and have incoming links from many different pages, and a publisher’s digital article repository can be licensed to any number of libraries.

Cities naturally emerge in places that can support life and commerce. Almost all major cities are built on coasts or rivers because water provides sustenance, transportation and commercial links, and power to enable industry. Many very old cities have crowded and convoluted street plans that do not seem intentionally organized, but grid plans in cities also have a very long history. Cities in the Middle East were laid out in rough grids as far back as 2000+ BCE. Using long axes was a way to create an impression of importance and power; consider all the long, wide roadways leading up to palaces, castles, or temples, which are often at the center of cities.

Because the United States, and especially the American West, was not heavily settled until much more recently and in a relatively short time period compared to most of Europe and Asia, it was a place for people to experiment with new ideas in urban design that were not possible in other places. The natural human tendency to impose order on habitation location had ample room to do just that. The easiest and most efficient way to organize space is using a coordinate grid, with streets intersecting at perpendicular angles. Salt Lake City, Albuquerque, Phoenix, and Seattle are notable examples of grid cities. An interesting hybrid structure exists in Washington DC, which has radiating diagonal avenues overlaid on a grid.47d[IA]

Built environments influence the expectations, behaviors, and experiences of everyone who enters the space—employees, visitors, customers, and inhabitants are all subject to the design of the spaces they occupy. These environments can be designed to encourage or discourage interactions between people, to create a sense of freedom or confinement, to reward exploration or enforce efficiency, and of course, much much more. The arrangement of the resources in a built environment also encourages or discourages interactions, and sometimes the built environment is designed with a specific collection of resources in mind to enable and reinforce some particular interaction goals or policies.

If we contrast the built environments of museums, casinos, hospitals, and airports, the way in which each of them facilitates or constrains interactions are more obvious. Museums are often housed in buildings designed as architectural monuments that over time become symbols of national, civic, or cultural identity. Many old art museums mimic classical architecture, with grand stairs flanked by tall columns. They have large and dramatic entry halls that invite visitors inside. Modern museums are decidedly less traditional, and today people in the museum world people talk about the “Bilbao effect,” referring to the marketing potential for a museum and its city when a famous architect creates an audacious design like Frank Gehry’s Guggenheim museum in that Spanish city, which has curved exterior walls that almost seem random. However, other people complain that the architecture of modern art museums can overshadow the art collection contained within because people are induced to pay more attention to the building than to its contents.

Some recently built airports have been designed with architectural flair, but airport design is more concerned with efficiency, walkability (maybe with the aid of moving walkways), navigability, and basic comfort for travelers getting in and out the airport. Wide walkways, multiple staircases, and people movers whose doors open in one direction at a time, all encourage people to move in certain directions, sometimes without the people even realizing they are being directed.

If we look at hospital emergency rooms we find (if money and time were available in the budget when they were designed) that they are set up to be easy to find from external transportation paths—in fact, the size and color of their external signs are regulated by standards. Additionally, a modern ER generally supports the staff having a clear view of the waiting room, provides areas for levels of triage, and seats people in such a way that they can be seen by those on duty.

If you have ever been lost in a casino or had trouble finding the exit you can be sure you experienced a casino that achieved its main design goals: keeping people inside and making it easy for them to lose track of time because they lack both windows and clocks. As American architect Robert Venturi points out, “The intricate maze under the low ceiling never connects with outside light or outside space...This disorients the occupant in space and time...He loses track of where he is and when it is.” The Venetian hotel in Las Vegas created an indoor Grand Canal that so closely mimics outdoor light and breezes it is easy to forget you have not left the casino. It makes strolling through the shops feel like a break from the rest of the environment even though you have not left the hotel.47e[Mus]

If one accepts the premise that values and bias are at work in decisions about organizing systems, it is difficult not to see it in built environments. Consider queue design in banks, supermarkets, or boarding airplanes. Assuming that it is desirable to organize people efficiently to minimize wait times and crowding, how should the queue be designed? How many categories of people should there be? What is the basis for the categories?

It may be uncontroversial to include several express lanes in a supermarket checkout, because people can choose to buy fewer items if they do not want to wait. Similarly, it seems essential for hospital emergency rooms to have a triage policy that selects patients from the emergency room queue based on their likely benefit from immediate medical attention.

However, consider the dynamic created by queue design at Disneyland to give priority to people with physical limitations and disabilities. This seemingly socially respectful decision was exploited by a devious collaboration between disabled people and wealthy non-disabled people who hired them to pose as family members, enabling the entire "family" to cut ahead of everyone else. In response, Disney modified the policy favoring disabled patrons, causing numerous complaints about Disney's insensitivity to their concerns.47f[IA]

There are many other examples of how values and biases become part of built environments. In the mid-20th century the road systems of Long Island in New York were designed with low overpasses, which prevented public buses from passing under them, effectively segregating the beaches. The trend in college campus design after the student protests of the 1960s and 1970s was to create layouts that would prevent or frustrate large demonstrations.47g[Phil]

It is easy to move through an environment and stay oriented if the design is simple and consistent, but most built environments must include additional features or descriptions to assist people in these tasks. Distinctive architectural elements can create landmarks for orientation, and spaces can be differentiated with color, lighting, furnishings, or other means. More ubiquitous mechanisms include signs, room numbers, or directional arrows highlighting the way and distance to important destinations.

In airports, for example, there are many orientation signs and display terminals that help passengers find their departure gates, baggage, or ground transportation services. In contrast, casinos provide little orientation and navigation support because increased confusion leads to lengthier visits, and more gambling on the part of the casino’s visitors.

A recent innovation in wayfinding and orientation mechanisms is to give them sensing and communication capabilities so they can identify people by their smartphones and then provide personalized directions or information. These so-called "beacon" systems have been deployed at numerous airports, including London's Gatwick, San Francisco, and Miami. 47h[IA]