Card sorting - Part 2

David Humphreys and Tania Lang
February 16 2009

This month we include the second article in a three-part series on card sorting by David Humphreys and Tania Lang and we share our tip of the month. See Part 1 for an introduction to card sorting.

Card sorting Part 2 - running a card sorting session

In Part 1 Introduction to card sorting, we outlined what card sorting is, the benefits and when to do this activity. In this edition, we will discuss some tips for running a card sorting session.

To run a card sorting session, you need a facilitator to run the sessions and collate the data (this can be two people but it is useful if one person is able to do both) and participants who represent the users on the site. Let's talk a little about each.

The facilitator

The facilitator's role is to:

  • welcome the participants
  • explain what they are going to do in the session
  • tell them the rules
  • help them when they get stuck or confused by individual cards, and
  • make sure the participants' writing can be read and that their groups make sense.

As facilitator it's likely that you will also be the person who is collating and analysing the data produced by the participants.

It's useful to have a second person in the room to help with participant questions and if possible, observe and learn from the process.

The participants

The participants should be representative of the users of your site – not staff! Unless staff are actual users of the site (such as for an intranet), we don't recommend using internal staff for card sorting as they are not representative of your external user population and often have a different mental model (i.e. think differently) about how the information should be sorted.

Depending on time and budget you can run a different card sorting session for different user groups on the site (such as prospective students and current students on a university website) to get a good picture of how their different mental models work. However if time and money are tight just getting a good mix of users in the room that is representative of the people using your site is a great start.

How many should I use?

We use 10 participants per session. Each session should have representative users of one user group although that is not always possible.

10 participants can usually generate enough content to work with however Jakob Nielsen recommends 15 users per group. Donna Spencer, Australian card sorting guru is happy with 10 but recommends 15 in 5 groups of 3 when performing group based card sorting.

The aim is to generate enough results that you have a good understanding of the patterns that emerge in the results and are comfortable with their repeatability.

Recruitment and venue

Recruitment can be a huge time-sink and a major headache. We use a Market Research firm because they have huge databases of potential participants and have the resources to recruit quickly and efficiently. However recruitment costs can be expensive, and if you are using external participants you will often need to pay them a small incentive just to show up. Only the most dedicated (or rabid!) customers are going to turn up for free.

Recruitment firms usually require about a week's lead time and if you are doing the recruitment yourself you should allow a similar time frame for a dedicated resource. Make sure you ring and confirm with all participants the day before the session.


You'll need a large room with a large amount of table space – enough for 10 large sheets of paper to be spread out on without crowding (we have had very unhappy participants in crowded table spaces). Ideally each person should have about a card table's space to spread out on.

The best layout for card sorting we recommend is a large conference room with tables in a U-shape or classroom style with plenty of space and little opportunity to see what other teams or individuals are doing. This is the ideal scenario but please be mindful of your participant's comfort. They will produce better results for you if they are happy. From our experience, board rooms with a long thin table down the middle are not great unless they are a really big organisation with a really big boardroom.

In our next issue, we will get into some tips and common traps for card sorting which can affect your results and outcomes.

Usability tip

Help users orient themselves within your site

Although it may be obvious to you how your site fits together, people who are visiting your site for the first time will often have no clue. And for many users coming in from search engines, the first page they see won't be your homepage - it could be any page on the site.

So make it easy for them to get a feel of your site as soon as they arrive:

  • Make sure every page has a clear heading;
  • Highlight the section that they're currently in on the navigation;
  • Consider using breadcrumbs to show users where they are in the site; and
  • Always help guide the user to the next step in their journey - whether that's calling, applying or viewing related content.
Categories: Card sorting,Information Architecture