15 years ago I had an idea, as many do. This was a new invention to solve the problem of backpack access, after seeing a struggling postman and my own frustrations. Although I'd collected an engineering degree way back, after a long career in media companies I had no expert knowledge of industrial design, backpacks or inventing. So on and off over the years the idea became a design doodle and then a couple of failed prototypes and then got filed away in a box. It collected dust but never left me, until I reached a turning point. After 2...

A great proposition and the P11 prototype works well, so we think. But the only way to truly test the concept and the product is to show 'the man in the street'. I hit the streets of London and ask people directly. Stopping busy Londoners is not a walk in the park, but outside St Paul's Cathedral holding up my sign, I wait for engagement. People's feedback is consistently positive, some of it exuberant. Messages about price are taken on board, but we come through the street jury with a clear endorsement. We are on course.

Intensive development in the studio and repeated testing continues. With all the feedback from the P7 focus groups, the P8 improvements are worthy of another formal round of consumer testing. The feedback is positive again and it is clear we should move to the next stage - finding a manufacturer. Luke's experience of bag manufacture is invaluable and we have introductory meetings with 3 strong manufacturing partners. The intense collaboration begins with our chosen partner and we start the process of building real samples of the backpack from a real factory.

More prototype development and we decide to put the P7 to the test. The first consumer focus groups pick over the prototype. It’s clear from the enthusiastic reactions that we’re addressing a real need in an innovative way. However, it is also crystal clear that there is a huge amount of work to do to make the user experience live up to the vision, and I realise that the original budget and timetable were hopelessly optimistic.