Over my 15 years of being involved with the early stages of the design process, there is one technique that I use time and time again.
It’s a technique that hones in on the characteristics of a concept by not only defining the things it is but also the things that it isn’t on the same continuum. I often don’t run this as an explicit workshop exercise but simply let the characteristics fall out by facilitating a discussion around purpose.
The end result is often a very simple table which contains a series of sets of characteristics, with each set being on the same continuum.
More recently I used this technique to define scope by defining the things that we are doing but also the things that are not doing.
It’s incredibly simple but in my experience capturing the isn’t terms is so powerful in really reinforcing the things that it is. So give it a try!