We help organisations construct large scale networks / distributed systems so that their performance and scalability properties are understood and can be managed. Our customers have ranged in size from 3 sites and 150 employees, to thousands of sites with 10+ million customers. They have included world class research organisations, major mobile and fixed line network operators and users of distributed systems where there are safety-of-life issues. These organisations have used our services as we are in the unique position to apply ex-ante performance engineering to their issues, and work with them to create affordable solutions, typically out of COTS.