UCD is a philosophy whereby the user is the focus of all design decisions. The extent to which real users should be involved in the design process tends to differ from practitioner to practitioner but that is not to say that the user’s best interests are not central to the design process in each UCD faction.

A significant part of UCD is establishing the needs of the user, this often includes focus groups, interviews and surveys.

Another technique is user testing on existing products in order to perform an evaluation of how well a product meets the needs of users. A number of users are recruited and then talked through processes by the “tester” in an environment closely matching the one in which the product will be used (such as a living room or workplace). This is not a test of the user but of how well the product works for the user in a real-life scenario. This technique can also be used in the earliest stages of development when the design of the system is still at prototype stage. Even paper prototypes can be useful in gaining an insight into how a product might be used or perceived by perspective users. The extent to which user testing is relied upon will differ from practitioner to practitioner.

Increasingly, the design community has relied on techniques under the umbrella of “contextual evaluation”, (Holtzblatt and Beyer 1993) which is a way of probing the activities of users while they carry out typical tasks in their usual environment. Techniques range from “Contextual Inquiry”, where the user is questioned and observed in context, to other more immersive techniques such as ethnography which involves much less interaction with the subject.

In addition to these methods, “card sorting” is a technique used (most notably) by information architects to find out how users categorise and group elements of the product’s architecture. For instance, in a card sort for a recruitment website the user may group “pay scales” and “tax” under “money”, indicating that in the navigation structure these two categories should be found under an umbrella heading of “money”. User’s needs as well as preferences are investigated with these exploratory techniques so that accessibility requirements can also be factored into the design.

UCD is not a methodology or a design lifecycle. There is no agreed definitive model of how a UCD design process should work (although many have been put forward). What is integral to UCD across the board is the focus on iterative design.

The UCD approach continues to gain prominence, particularly in the area of digital applications.