These icons are initial prototypes of a visual language for signage in the public realm that alerts the public to the presence of a digital technology. The black hexagons express the purpose of the technology; the blue and yellow hexagons show how identifiable information is used; and the white hexagons display the entity responsible for the technology. Another white hexagon with a QR code and URL enables people to learn more. (Image: Sidewalk Labs)

How can we bring transparency to urban tech? These icons are a first step.

Our “Digital Transparency in the Public Realm” project brought people around the world together to co-create a visual language to demystify the tech in cities.


2020 UPDATE: Please note that the open-source project DTPR is now independent of Sidewalk Labs and being stewarded by Helpful Places and an emerging coalition of partners and collaborators. For more information on the DTPR standard, please see this external website.

This post was co-written by Principal Designer Patrick Keenan and Legal Associate Chelsey Colbert.

Digital technology is all around us, but often invisible. Consider: on any one urban excursion (your commute, perhaps), you could encounter CCTVs, traffic cameras, transit card readers, bike lane counters, Wi-Fi access points, occupancy sensors that open doors — potentially all on the same block.

Many of these new innovations are exciting. After all, they can make public spaces more comfortable, responsive, and efficient. But there’s little transparency about what data these technologies are collecting, by whom, and for what purposes. Signage that does appear in the public realm often contains either small snippets, which give no indication of how to follow up or ask more questions, or multiple paragraphs of dense text.

That’s a problem. Consider the digital technologies we experience online. Research has shown that few users read long, jargon-filled privacy and data collection policies, leaving users to consent to digital technologies without a full understanding of their implications or trade-offs — and unable to provide feedback or ask questions.

A movement toward digital transparency can help by providing easy-to-understand language that clearly explains data and privacy implications of digital technologies. Digital transparency can empower users to meaningfully engage in what is fast-becoming a critical conversation of our time. And, equally important, transparency can nudge both users and data collectors towards best practices.

As digital technologies become increasingly embedded into our physical spaces, we can bring digital transparency to the public realm — an opportunity that has been identified as critical by academics, cities, and civic groups around the world.

But how do we start? Cities like Boston and London have already taken important first steps by posting clear signage whenever they employ digital technologies in the public realm. Similarly, regulatory entities in both the E.U. and the U.S. have called for the development of icons to communicate key terms and concepts around online privacy in a clear and digestible manner.

That would certainly help. Design languages already help generate understanding around complex issues every day. Nutrition labels help demystify the content of the foods we consume; Creative Commons logos quickly convey the key elements of their copyright licenses; and universal symbols help us effectively navigate through transportation hubs anywhere in the world.

“We’re far from the days where signs needed to convey simple ideas like stop or go. Our public realm has become more complex and oversaturated with signs and informational cues. New technology requires a richer visual language with roots in visual systems we already understand. It requires the knowledge and ideas of a wide range of experts, an iterative and collaborate process and an obsession with getting it right.”

— Spencer Cathcart, Creative Director, Puncture Design

There are also great precedents of digital technologies embedded in physical places that create more enriching and inclusive experiences. At 307, our workplace in Toronto, navigational beacons installed by CNIB and BlindSquare help people who are visually-impaired find their way around the space and learn more about the explorations on display. Physical signs can become digital doorways, opening up new channels of information.

A co-design session for Digital Transparency in the Public Realm at 307, Sidewalk Labs’ experimental workspace in Toronto. (Image: Sidewalk Labs)

We strongly believe that people should know how and why data is being collected and used in the public realm, and we also believe that design and technology can meaningfully facilitate this understanding. For these reasons, we embarked on a collaborative project to imagine what digital transparency in the public realm could be like.

Together with more than 100 participants from several cities, we sketched, debated, iterated, and prototyped a visual language that offers a quick way to understand the technology around us — and a means to easily learn more. (Learn all about that co-creation process, which included co-design sessions, user research, and more, here.)

“It was great to bring together people with different perspectives, including government representatives and disability activists, for a day of conversation, deliberation and design.”

– Cath Richardson, Research Lead, Projects by IF

Today we’re excited to share our initial prototypes: a starting point for what we hope will be a much larger conversation.

Visual Language

From our user research, we knew that there were some core concepts that people wanted to know while they were in the public realm: specifically, the purpose of a digital technology as well as its accountable entity. People also wanted to have an easy way to follow-up and learn more and know if the technology could “see” or identify them.

We decided to convey each of these concepts in an icon that would be placed within a hexagon. We chose hexagons because, as a visual cue, they are not widely used today in public realm signage to represent other concepts. They are also easy to combine together in different ways, enabling some close concepts to live together visually.

Example of how the icons are in use with a pilot deployment of Numina at 307, Sidewalk Labs’ experimental workspace in Toronto. Numina is a technology company that uses a privacy-by-design approach to measure the flows of people and differentiated transportation modes through streets and open spaces, to assist urban planners in designing more human-scale environments. (Image: Sidewalk Labs)

One hexagon conveys the purpose of the technology; another, the logo of the entity responsible for the technology; and a third contains a QR code that takes the individual to a digital channel where they can learn more. (We’re currently working on a system to make the QR code easy to generate, so stay tuned for that!)

The final piece of essential information we wanted to convey — which was echoed strongly by the user research participants — involved privacy. In situations where identifying information is collected, a privacy-related colored hexagon would also be displayed. This hexagon would combine an icon displaying the technology type (video, image, audio, or otherwise) with an icon expressing how identifiable information is used (yellow for identifiable, blue for de-identified before first use, among others). When you are not identifiable, you don’t see this hexagon.

A Digital Channel for Learning More

The QR code links the physical sign in the public realm to a digital channel that conveys much more information about the technology and provides a mechanism for people to provide feedback. (Image: Sidewalk Labs)

With the core concepts represented on the sign, and the QR code to bridge the physical and the digital, the remainder of the information about the technology could be made available on the digital channel.

Because the nuances of data custody and sensing technology can be complex and overwhelming to understand, we felt we needed to provide a consistent, linear way to organize and present information on this digital channel. So we designed a system of icons that chain together.

The visual system provides a consistently organized way to present information about the digital technology, starting with the purpose and the technology type, through details about the data and how it is processed, and ending with storage and access. (Image: Sidewalk Labs)

The chain contains three categories of information: the hardware and purpose of the technology, the software and data it uses, and the means of storage. Each category is represented by a different shape.

The chain begins with icons conveying the responsible organisation, the purpose the technology serves, and the type of technology it is; this information is contained in hexagons (mirroring the signs observed in the physical world).

The following icons convey whether the data collected is identifiable, how it is processed, and who has access to the data; this information is contained in circles (representing the idea that the use and handling of data should be a continual activity).

Finally, the last icons convey where the data is stored and who has access to it; this information is conveyed in squares (because we often store things in boxes).

“Our vision has always been to be transparent and pedestrian-centric in the way we design and deploy technology in public spaces — and to have a voice in shaping the standards and best practices for how smart cities technologies are layered into cities and neighborhoods. This is why we jumped at the opportunity to collaborate and look forward to testing this design system with everyone.”

— Sandra Richter, CEO, Soofa

What comes next?

Sidewalk Labs’ is making these concepts, including all the workshop activities and materials, publicly and freely available for others to adopt, use and build upon, so that we all can advance digital literacy and help people understand digital infrastructure in the public realm.

We are excited to announce the release of the first draft of these design patterns, which can be found in the DTPR repository on Github. We are also making the co-design facilitation guide and all the materials you might need to run your own sessions publicly available, so that anyone, anywhere, can bring together a group of folks to engage with this topic.

We’ve already heard from participants who have committed to testing this visual language in multiple cities, and we’d love to hear from more. If you live in Toronto or are nearby our office on 307 Lakeshore Boulevard East, come on by and test out the signage in person. We’ll be continuing to refine the signs, the icons, and the digital channel based on feedback from visitors.

“We stand at a critical point in the development of our cities where technology is increasing all around us — yet most of us are oblivious to how this technology is being used and to what ends. This is a global challenge and we need global solutions. I commend all of our colleagues from civil society, government and the private sector who have come together to co-design these initial prototypes. Now it’s time to test, iterate and put these concepts into action.”

–Jeff Merritt, Head of IoT, Robotics and Smart Cities, World Economic Forum

In the coming weeks, we’ll be working on a digital solution that makes it easy for space managers to create their own signage with QR codes. Though we’re excited about where this ends up, we know this project’s future requires diverse organizations coming together to address this challenge. If you know an organization or institution with a mission that aligns with this work, please get in touch by emailing us at

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Jacqueline Lu
Sidewalk Talk

i build new nervous systems from tech+data. Leading Helpful Places and stewarding DTPR. Data Lead @mozilla. Alum @SidewalkLabs @NYCParks.