Book Review: ‘Mismatch’ by Kat Holmes

I picked up the book Mismatch – How Inclusion Shapes Design, by Kat Holmes, as part of my User Experience Design Masters study. Published by MIT press, it’s considered a strong starting point for design students and practitioners who want to better understand inclusion in design. As a fledgling UX designer with an intention to design for projects for social good, it felt like an important read. Kat is an engineer turned designer who headed up the inclusive product innovation at Microsoft for 7 years and went on to Google as UX design director. She has dedicated her career to understanding the true scope of human diversity, studying different ways in which people can feel excluded by design with the view to make a shift from the concept of inclusive design as ‘nice add-on’ to a culture of design in which inclusivity is embedded at every stage.

Kat defines Inclusive design as: A methodology that enables and draws on the full range of human diversity. Most importantly, this means including and learning from people with a range of perspectives.


Drawing from the ‘Nothing about us, without us’ slogan popularised in America by disability activist and author James Charlton in the late 1990’s, Kat continually reiterates throughout the book that the job of a designer is to involve the end user at each stage of the design journey. She creates a 5-step circle of inclusion to be integrated into the design process. Whether architects, urban planners, product designers or technologists, our design decisions influence who can contribute to society, and whether those interactions are easy, stressful, fun or challenging. The first part of the book guides the reader to recognise exclusion  – as this is the first stem to understanding inclusion.


Kat Holmes | We Design Online Exhibition - Design Museum Everywhere


Redefining the term inclusion, who is excluded and why

One of the book’s key missions is reframing the way readers consider ‘disability’. Moving away from the binary narrative of ‘able’ and ‘disabled’, we’re introduced to the spectrum of ability or ‘the persona spectrum’; “An inclusive design method that solves for one person and then extends to many”. Examples of products designed for a specific need and then extended to be invaluable to users outside that spectrum are endless. Captioning and subtitles designed for the hard of hearing are valued by people in noisy spaces, or people learning a new language. The flexible straw was designed by father Joseph Friedman to help his daughter drink a milkshake at a high table and is now a useful tool for millions, for people who are bed-bound, to those sipping cocktails on the beach. Mismatch asks us to consider designing for inclusivity as an opportunity for innovation and divergent thinking, rather than an afterthought aimed at a sub-group.

It’s important to remember here that we may have been educated to design using a framework of ‘the normal human’. Certainly in my fashion design education I can tell you that the idea of fit models and mannequins exclude 99.9% of the population when designing initial prototypes. It begs the question, why even start with this restricted vision of the human body? Thankfully this is being challenged, and there are even people in fashion looking to User Experience Design methodology as a reference to consider widening that scope.

Many design techniques to envision masses of people are still influenced by the 19th century Belgian mathematician Quetelet, the creator of The Bell Curve. Drawing from models of probability established decades earlier, Quetlet gathered data on human bodies, plotted it on a chart and defined the middle curve as ‘normal’, otherwise known as the 80/20 rule – the centre of the 80% defining the average. His consequent publication Treatise on Man held that individuals should be measured against this perfect average. The bell curve was used as the basis for varied fields of study, including body mass index, public health and the horrific assertions of Eugenics. “The power of the bell curve echoes through the design of our society, from classrooms to computers”.  This approach fails to recognise the nuance of human ability, diversity and our changing facets. Of course there are occasions where we need to measure averages and discover popular consensus, however Kat encourages designers to err away from presumptions. “This leads many teams to treat the remaining 20% as outliers of edge cases… in fact edge cases can be a useful starting point for creating better solutions”.

Reading this book from the perspective of a UX designer, I see the methodologies and ways of thinking as key to our practice. The book provides a framework for designing beyond our societal structure, which currently prioritises a ‘perfect’ kind of human. ‘The Measure of Man’, published in 1960 laid out the ‘average’ proportions of men and women, and is still a reference to many designers to this day. The book points out that we’ve got a long way to go in creating a society that doesn’t exclude people. Holmes summarizes a process that can be applied to various industries that require working with a large population. Not just for designers, but for anyone who’s job includes human interaction, Mismatch challenges us to identify our own biases. This book challenges designers to think outside their own sensory experience and design for a fairer future.


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