3SL (Structured Software Systems Ltd) is a group of engineers who share a fervent desire to help other engineers build systems more easily, efficiently and quickly. We do this by producing the best software tools that we can, and by doing everything possible to help you, our fellow engineers, to use our tools as effectively as possible.
We hope that our tools will help engineers across the entire lifecycle of their products, to make the right products, for the right needs, in the right timescale.
"Cradle" is how we provide our tools as a product. The goals for Cradle have grown, broadened and matured over the many years that Cradle has been in use. Our latest Cradle-7 product is the closest that we have yet come to fulfilling our goals for an integrated requirements management and systems engineering environment.
We hope that if you use Cradle, you will join the many engineers from a wide variety of industries whose expertise and experience informs our goals, and guides the evolution of Cradle’s features, usability and technologies.
3SL was founded in 1987 by Mark Walker when his ideas for a systems engineering tool were not shared by his employer and he left to try to realise his vision alone. From this tiny start, Mark has been joined by a worldwide team of engineers who have transformed his initial ideas into the Cradle product that we offer to you today.
3SL is based in Barrow-in-Furness, a small town in the North West of England that was known for commercial and naval shipbuilding and a wide range of engineering products, and is now best known for the nuclear submarines built here for the Royal Navy.
Cradle was first exhibited in 1989 and first sold to a local university later that year. Exclusive rights to distribute Cradle were acquired by Yourdon, a US company later bought by the French company CGI. The relationship between 3SL and CGI ended in the late 1990s. Since then, 3SL has offered Cradle directly and through our partners.
3SL was established in the US in 1998, originally in Baltimore, MD and then in Huntsville, AL where we remain today. Huntsville has a worldwide reputation for its large number of major engineering companies and in particular for its space industries working with NASA at the Marshall Space Flight Center. 3SL has particularly strong links to NASA, not only in Huntsville, but across all of NASA’s many locations.
3SL has grown a worldwide network of partners who offer Cradle and their own engineering services. Each partner has considerable engineering skills and a wide range of experience in industries ranging from aerospace, automotive, defence, manufacturing, power generation and pharmaceuticals to rail, oil and gas, nuclear engineering and academic research. Please see our contact page for further details.