Creating a modular design system for a famed travel tech company 


We designed a fully customizable flight booking system for airlines across the globe.




A frequent flight companion

SITA is one of the world’s oldest travel IT companies, providing services to over 400 airlines and affiliates worldwide. Their flagship product, the web-based flight search and reservation system Horizon, is used by companies across six continents, each with custom branding, language, cultural norms, and accessibility requirements.

Expanding the horizon

To stay competitive in an ever-demanding market and move away from legacy systems, SITA wanted to evolve Horizon into a flexible platform that would meet the needs of both their airline customers and end-users. Working closely with SITA’s stakeholders, we created a fully modular design system that not only meets their current requirements but is also extendable to new products and services.

Languages supported16
Unique components created as part of design system36
SITA’s airline customers using Horizon130


A multi-faceted product for the airline industry

Developing a cohesive design system for a multi-faceted industry product requires agency and client to respond to multiple challenges at every turn.


Legacy systems

Backend systems built years ago are still widespread in the industry, despite losing their practical usability.


All processes are governed by complex business requirements based on an array of international rules and regulations.

Tight margins

Fierce competition in the industry and razor-thin profit margins require innovative ways of generating revenue.


Multinational scale

Due to SITA’s many partners and products, our process included 34 direct stakeholders across six time zones – all with the ability to pull the brake handle.

Legacy design methods

Many of SITA’s products were launched before the widespread uptake of user-centered design practices. The interfaces had usability issues resulting from years of bolting new features and functionality onto legacy designs.

Horizon product line

Lack of flexibility

As with many of SITA’s other products up to this point, Horizon was built using a classic waterfall methodology.

Unmet user needs

The development practices employed resulted in a product that was misaligned with the needs of its user base.

Inability to update

Without the possibility to iterate quickly, releasing updates became difficult and time consuming, and the customers were kept waiting.

Building such a complex system with so many unique challenges required a massive discovery effort. We talked to nearly 40 stakeholders over eight weeks, performed heuristic analysis, competitive analysis, user research, and held “Airlines 101” sessions, all of which resulted in a detailed report containing the roadmap to creating the new product.

SITA was eager to adopt an Agile methodology, and the Horizon project was an ideal starting point.

Building the design system, we employed the user-centered, iterative cycle:


A chameleon platform to get all users aboard

A single platform had to serve both customers and ticketing agents, meeting the unique needs of both groups. At the same time, it had to be easily adaptable for any of 130 SITA’s airline clients on six continents.

A global solution requires global research – we conducted extensive field studies, ideation workshops and usability tests with ticketing agents and airline stakeholders in the US, Canada, and India.


Altitude, a single source of truth for all their design needs.

To provide the SITA team with everything they needed to apply the principles of user-centered design to the design system we developed for Horizon, we created Altitude – a single source of truth for all their design needs. 

Thanks to Altitude, SITA was able to bring the design system in-house and continue to update Horizon after we finished our work on the project. It also laid the groundwork for applying the design system to other products in their portfolio, ultimately allowing the creation of a cohesive design system to be applied across the full suite of SITA products.

Included in Altitude

Why-To” guidance illustrating design principles in practice, user-centered design best practices, error handling, and messaging.

How-To” guidance including the usage of colors, type, icons, layout grid, and UI elements

HTML, CSS, and JS markup for all commonly used UI components

The team brought how the consumer FEELS front and centre in UX design, and this is something that became ingrained.


SITA immediately adopted, and continues to evolve Altitude, along with its design principles company-wide. Setting a new course – forward, they immediately started onboarding their customers to the newly designed Horizon platforms.

This project was executed by our US team, formally known as ETR. The company was acquired by Infinum in 2023.

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