There is a worrying trend emerging in the field of information architecture: organisations are attempting to finalise site structures without evaluating their effectiveness in the context of a web page.

Card sorting and card-based classification provide excellent insights into the inherent structure behind content. Both are excellent tools for defining strict taxonomies, but they do not necessarily generate the most approachable structure for a site. Content centred design is not necessarily user centred design.

The site structure should be considered in context

Browser windows impose many limitations, one of the most obvious is space. Failure to consider the reality that the site structure must function in the context of a browser window, can result in the following problems:

• The site structure has too many top-level headingsHorizontal navigation only allows for around eight top level headings. Vertical navigation allows for slightly more headings.
• Heading titles are too longDescriptive heading titles are best, but the limited space on a web page (particularly horizontally) means that compromises often need to be made.

These factors mean that the site structure derived from abstract exercises, such as card-based classification evaluation, may not successfully transfer to the web.

Structure isn’t the only way people navigate sites

The site structure is only one of many factors that influence how people navigate a site.

• Information scent has a significant impact on whether a site is easy or difficult to navigate.Even sites with good structures are likely to be difficult to navigate without strong information scents. (See the earlier article Information scent: helping people find the content they want for more on information scent)
• Deep links enable people to move from top-level pages to low-level content without using the site structure.
• Related links enable people to move across the site oblivious to their absolute position in the hierarchy of the site.

Finalising the site structure without considering the potential impact of these factors can result in an unnecessarily bloated site structure.

Take an iterative approach

The best solution is to take an iterative approach to defining the site structure and page layouts.

1. Conduct card sorting sessions to understand how representative users perceive the inherent structure behind the proposed content.
2. Create a draft site structure.
3. Evaluate the draft site structure using card-based classification evaluation.
4. Revise the site structure so it works as a navigation system within the confines of a web page.
5. Create further page layouts to support user scenarios. Consider the role of information scent, deep links and related content.
6. Evaluate the page layouts, ideally through usability testing.
7. Continue to prototype, evaluate and revise the site structure and page layouts until you are happy with the results.

At the end of this process you should finalise and document the site structure and page layouts.

Don’t stop doing card sorting and card-based classification evaluation

The intention of this article isn’t to stop people conducting card sorts and card-based classification evaluations. These are excellent techniques for understanding how different people perceive the inherent structure behind content, but they do not consistently produce effective site structures.